JSON Component
Properties Methods Events Config Settings Errors
The JSON component can be used to parse and write JSON documents.
Syntax
nsoftware.IPWorks.JSON
Remarks
The JSON component offers a fast and simple way to parse and write information in JSON documents.
Parsing JSON
The JSON component parses JSON documents and verifies that they are well-formed. The results are provided through a set of events.
In addition, the document structure may be queried through an XPath mechanism that supports a subset of the XPath and JSONPath specification.
The parser is optimized for read applications, with a very fast engine that builds internal DOM structures with close to zero heap allocations. Additionally, BuildDOM can be set to False, which reduces the overhead of creating the DOM and offers a fast forward-only parsing implementation that fires events to provide the parsed data.
When parsing a document, events will fire to provide information about the parsed data. After Parse returns the document, it may be navigated by setting XPath if BuildDOM is True (default). If BuildDOM is False, parsed data are accessible only through the events.
The following events will fire during parsing:
If BuildDOM is True (default), XPath may be set after this method returns. XPath may be set to navigate to specific elements within the JSON document. This will be the path to a specified value within the document. Because arrays in JSON only contain values, and no associated object name, an empty name will be used for these values. To reach an array element at position 1, the path must be set to "[1]". In addition, a root element named "json" will be added to each JSON document in the parser.
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
The XPath property accepts both XPath and JSONPath formats. Please review the following notes on both formats.
XPath
The path is a series of one or more element accessors separated by '/'. The path can be absolute (starting with '/') or relative to the current XPath location.
The following are possible values for an element accessor:
'name' | A particular element name. |
[i] | The i-th subelement of the current element. |
.. | the parent of the current element. |
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
Simple JSON Document
{ "firstlevel": { "one": "value", "two": ["first", "second"], "three": "value three" } }Example 1. Setting XPath:
Document root | JsonControl.XPath = "/" |
Specific Element | JsonControl.XPath = "/json/firstlevel/one/" |
i-th Child | JsonControl.XPath = "/json/firstlevel/two/[i]/" |
JSONPath
This property implements a subset of the JSONPath notation. This may be set to point to a specific element in the JSON document.The JSONPath is a series of one or more accessors in either dot-notation
$.store.book[0].titleor in bracket-notation, as follows:
$['store']['book'][0]['title']
After setting XPath, the following properties are populated:
Example 2. Setting JSONPath:Given the following JSON document:
{ "store": { "book": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "isbn": "0-553-21311-3", "price": 8.99 }, { "category": "fiction", "author": "J. R. R. Tolkien", "title": "The Lord of the Rings", "isbn": "0-395-19395-8", "price": 22.99 } ], "bicycle": { "color": "red", "price": 19.95 } }, }The following code shows several examples.
Get the first book's author:
json.XPath = "$.store.book[0].author";
Console.WriteLine(json.XText);
//Output
//"Nigel Rees"
Select the first book and inspect the children:
json.XPath = "$.store.book[0]";
Console.WriteLine("Child Count: " + json.XChildren.Count);
Console.WriteLine(json.XChildren[1].Name + ": " + json.XChildren[1].XText);
//Output
//Child Count: 4
//author: "Nigel Rees"
Get the price of the second book:
json.XPath = "$['store']['book'][1]['price']";
Console.WriteLine(json.XText);
//Output
//12.99
Get the second to last book's author:
json.XPath = "$['store']['book'][last() - 1]['author']";
Console.WriteLine(json.XText);
Console.WriteLine(json.XPath); //Note that "last() - 1" is resolved to "3".
//Output
//"Herman Melville"
//$['store']['book'][3]['author']
Display the full subtree at the current path:
json.XPath = "$.store.book[0]";
Console.WriteLine(json.XSubTree);
//Output
// {
// "category": "reference",
// "author": "Nigel Rees",
// "title": "Sayings of the Century",
// "price": 8.95
// }
Input Properties
The component will determine the source of the input based on which properties are set.
The order in which the input properties are checked is as follows:
When a valid source is found, the search stops.If parsing multiple documents, call Reset between documents to reset the parser.
Writing JSON
The JSON component also can be used to create a JSON document.
The document is written to the selected output property. In addition, as the document is written, the JSON event will fire. The Text event parameter contains the part of the document currently being written.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
Example. Writing a JSON Document:
Writing a simple JSON document describing a pet:
Json json = new Json();
json.OutputFile = "C:\\temp\\fido.json";
json.StartObject();
json.PutProperty("name", "fido", 2);
json.PutName("previousOwners");
json.StartArray();
json.PutValue("Steve Widgetson", 2);
json.PutValue("Wanda Widgetson", 2);
json.PutValue("Randy Cooper", 2);
json.PutValue("Linda Glover", 2);
json.EndArray();
json.PutProperty("weightUnit", "lbs", 2);
json.PutProperty("weight", "62", 3);
json.EndObject();
json.Flush();
This example results in the following JSON:
{ "name": "fido", "previousOwners": [ "Steve Widgetson", "Wanda Widgetson", "Randy Cooper", "Linda Glover" ], "weightUnit": "lbs", "weight": 62 }
When writing multiple documents, call Reset between documents to reset the writer.
Modifying JSON
The JSON component also allows for modifying existing JSON documents. After loading a JSON document with Parse the document may be edited. The component supports inserting new values, renaming or overwriting existing values, and removing values. After editing is complete, call Save to output the updated JSON document.
The following methods are applicable when modifying a JSON document:
When Save is called, the modified JSON is written to the specified output location.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
Example 1. Inserting New Values:
To insert new values in a JSON document, first load the existing document with Parse. Next set XPath to the sibling or parent of the data to be inserted. Call InsertProperty or InsertValue and pass the ValueType and Position parameters to indicate the type of data being inserted and the position.
The ValueType parameter of these methods specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
The Position parameter of these methods specifies the position of Value. Possible values are as follows:
- 0 (Before the current element)
- 1 (After the current element)
- 2 (The first child of the current element)
- 3 (The last child of the current element)
For example:
Given the following JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", } ] } }
Insert a new property "price" for each book:
json.XPath = "/json/store/books/[1]";
json.InsertProperty("price", "8.95", 3, 3); //3 - Number, 3 - Last Child
json.XPath = "/json/store/books/[2]";
json.InsertProperty("price", "12.99", 3, 3); //3 - Number, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 } ] } }
To add a new book to the array:
json.XPath = "/json/store/books";
json.InsertValue("", 0, 3); //0 - Object, 3 - Last Child
json.XPath = "/json/store/books/[3]";
json.InsertProperty("category", "fiction", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("author", "Herman Melville", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("title", "Moby Dick", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("price", "8.99", 3, 3); //3 - Number, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
To add a new array property to each book:
json.XPath = "/json/store/books/[1]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[1]/tags";
json.InsertValue("quotes", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("british", 2, 3); //2 - String, 3 - Last Child
json.XPath = "/json/store/books/[2]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[2]/tags";
json.InsertValue("trilogy", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("war", 2, 3); //2 - String, 3 - Last Child
json.XPath = "/json/store/books/[3]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[3]/tags";
json.InsertValue("classic", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("whales", 2, 3); //2 - String, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["quotes", "british"], "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "tags": ["trilogy", "war"], "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
Example 2. Removing Values:
To remove existing values, set XPath and call the Remove method. Continuing with example 1, to remove
the first book:
json.XPath = "/json/store/books/[1]";
json.Remove();
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["trilogy", "war"], "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
To remove the "category" properties from each book:
json.XPath = "/json/store/books/[1]/category";
json.Remove();
json.XPath = "/json/store/books/[2]/category";
json.Remove();
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["trilogy", "war"], "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
Example 3. Updating Existing Names and Values:
The SetName and SetValue methods may be used to modify existing names and values. Continuing with the preceding JSON in example 2, to rename "tags" to "meta" and update values within the array and prices:
//Rename "tags" to "meta" for 1st book
json.XPath = "/json/store/books/[1]/tags";
json.SetName("meta");
//Update Price
json.XPath = "/json/store/books/[1]/price";
json.SetValue("13.99", 3); //3 - Number
//Rename "tags" to "meta" for 2nd book
json.XPath = "/json/store/books/[2]/tags";
json.SetName("meta");
//Update tag "whales" to "revenge"
json.XPath = "/json/store/books/[2]/meta/[2]";
json.SetValue("revenge", 2); //2 - String
//Update Price
json.XPath = "/json/store/books/[2]/price";
json.SetValue("9.99", 3); //3 - Number
json.Save();
Produces the JSON:
{ "store": { "books": [ { "meta": ["trilogy", "war"], "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 13.99 }, { "meta": ["classic", "revenge"], "author": "Herman Melville", "title": "Moby Dick", "price": 9.99 } ] } }
Property List
The following is the full list of the properties of the component with short descriptions. Click on the links for further details.
BuildDOM | When True, an internal object model of the JSON document is created. |
InputData | This property includes the JSON data to parse. |
InputFile | This property specifies the file to process. |
OutputData | This property includes the output JSON after processing. |
OutputFile | This is the path to a local file where the output will be written. |
Overwrite | This property indicates whether or not the component should overwrite files. |
Validate | This property controls whether documents are validated during parsing. |
XChildren | This property includes a collection of child elements of the current element. |
XElement | This property includes the name of the current element. |
XElementType | This property indicates the data type of the current element. |
XErrorPath | This property includes an XPath to check the server response for errors. |
XParent | The parent of the current element. |
XPath | This property provides a way to point to a specific element in the response. |
XSubTree | This property includes a snapshot of the current element in the document. |
XText | This property includes the text of the current element. |
Method List
The following is the full list of the methods of the component with short descriptions. Click on the links for further details.
Config | Sets or retrieves a configuration setting. |
EndArray | This method writes the closing bracket of a JSON array. |
EndObject | This method writes the closing brace of a JSON object. |
Flush | This method flushes the parser's or writer's buffers. |
HasXPath | This method determines whether a specific element exists in the document. |
InsertProperty | This method inserts the specified name and value at the selected position. |
InsertValue | This method inserts the specified value at the selected position. |
Parse | This method parses the specified JSON data. |
PutName | This method writes the name of a property. |
PutProperty | This method writes a property and value. |
PutRaw | This method writes a raw JSON fragment. |
PutValue | This method writes a value of a property. |
Remove | This method removes the element or value set in XPath. |
Reset | This method resets the component |
Save | This method saves the modified JSON document. |
SetInputStream | This method sets the stream from which the component will read data to parse. |
SetName | This method sets a new name for the element specified by XPath. |
SetOutputStream | This method sets the stream to which the component will write the JSON. |
SetValue | This method sets a new value for the element specified by XPath. |
StartArray | This method writes the opening bracket of a JSON array. |
StartObject | This event writes the opening brace of a JSON object. |
TryXPath | This method navigates to the specified XPath if it exists. |
Event List
The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.
Characters | This event is fired for plaintext segments of the input stream. |
EndDocument | This event fires when the end of a JSON document is encountered. |
EndElement | This event is fired when an end-element tag is encountered. |
Error | Fired when information is available about errors during data delivery. |
IgnorableWhitespace | This event is fired when a section of ignorable whitespace is encountered. |
JSON | This event fires with the JSON data being written. |
StartDocument | This event fires when the start of a new JSON document is encountered. |
StartElement | This event is fired when a new element is encountered in the document. |
Config Settings
The following is a list of config settings for the component with short descriptions. Click on the links for further details.
CacheContent | If true, the original JSON is stored internally in a buffer. |
Charset | Specifies the charset used when encoding data. |
CloseInputStreamAfterProcess | Determines whether or not the input stream is closed after processing. |
CloseOutputStreamAfterProcess | Determines whether or not the output stream is closed after processing. |
ElementXPath | The XPath value for the current element in the document. |
EscapeForwardSlashes | Whether to escape forward slashes when writing a JSON object. |
InputFormat | Specifies the input format used in JSON streaming. |
PrettyPrint | Determines whether output is on one line or "pretty printed". |
RecordEndDelimiter | The character sequence after the end of a JSON document. |
RecordStartDelimiter | The character sequence before the start of a JSON document. |
StringProcessingOptions | Defines options to use when processing string values. |
XPathNotation | Specifies the expected format when setting XPath. |
BuildInfo | Information about the product's build. |
GUIAvailable | Whether or not a message loop is available for processing events. |
LicenseInfo | Information about the current license. |
MaskSensitiveData | Whether sensitive data is masked in log messages. |
UseInternalSecurityAPI | Whether or not to use the system security libraries or an internal implementation. |
BuildDOM Property (JSON Component)
When True, an internal object model of the JSON document is created.
Syntax
Default Value
True
Remarks
Set this property to True when you need to browse the current document through XPath.
InputData Property (JSON Component)
This property includes the JSON data to parse.
Syntax
Default Value
""
Remarks
This property specifies the JSON to be processed. Set this property before calling Parse.
This may be set to a complete JSON document, or partial data. When setting partial data, call Parse after each chunk of data is set. For instance:
//Parse the following in chunks: { "data": 1}
json.InputData = "{ \"data\""
json.Parse();
json.InputData = ": 1}"
json.Parse();
Input Properties
The component will determine the source of the input based on which properties are set.
The order in which the input properties are checked is as follows:
- SetInputStream
- InputFile
- InputData
InputFile Property (JSON Component)
This property specifies the file to process.
Syntax
Default Value
""
Remarks
This property specifies the file to be processed. Set this property to the full or relative path to the file that will be processed.
After setting this property, call Parse to parse the document.
Input Properties
The component will determine the source of the input based on which properties are set.
The order in which the input properties are checked is as follows:
- SetInputStream
- InputFile
- InputData
OutputData Property (JSON Component)
This property includes the output JSON after processing.
Syntax
Default Value
""
Remarks
This property contains the resultant JSON after processing.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
OutputFile Property (JSON Component)
This is the path to a local file where the output will be written.
Syntax
Default Value
""
Remarks
This property specifies the file to which the output will be written. This may be set to an absolute or relative path.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
Overwrite Property (JSON Component)
This property indicates whether or not the component should overwrite files.
Syntax
Default Value
False
Remarks
This property indicates whether or not the component will overwrite OutputFile. If Overwrite is False, an error will be thrown whenever OutputFile exists before an operation. The default value is False.
Validate Property (JSON Component)
This property controls whether documents are validated during parsing.
Syntax
Default Value
True
Remarks
When true (default), the document will be validated during parsing. To disable validation set Validate to false. Disabling validation may be useful in cases in which data can still be parsed even if the document is not well formed.
XChildren Property (JSON Component)
This property includes a collection of child elements of the current element.
Syntax
public JSONElementList XChildren { get; }
Public Property XChildren As JSONElementList
Remarks
This property contains a collection of child elements of the current element. The elements are provided in the collection in the same order they are found in the document.
This collection is indexed from 0 to count -1.
This property is not available at design time.
Please refer to the JSONElement type for a complete list of fields.XElement Property (JSON Component)
This property includes the name of the current element.
Syntax
Default Value
""
Remarks
This property contains the name of the current element. The current element is specified through the XPath property.
XElementType Property (JSON Component)
This property indicates the data type of the current element.
Syntax
public JSONXElementTypes XElementType { get; }
enum JSONXElementTypes { etObject, etArray, etString, etNumber, etBool, etNull }
Public ReadOnly Property XElementType As JsonXElementTypes
Enum JSONXElementTypes etObject etArray etString etNumber etBool etNull End Enum
Default Value
0
Remarks
This property specifies the data type of the current element. After setting XPath, this property is populated. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
Note: This property is not applicable when parsing a document and BuildDOM is False.
This property is read-only.
XErrorPath Property (JSON Component)
This property includes an XPath to check the server response for errors.
Syntax
Default Value
""
Remarks
This property contains an XPath to check the server response for errors. If the XPath exists, an exception will be thrown containing the value of the element at the path.
XParent Property (JSON Component)
The parent of the current element.
Syntax
Default Value
""
Remarks
This property contains the parent of the current element. The current element is specified via the XPath property.
This property is read-only.
XPath Property (JSON Component)
This property provides a way to point to a specific element in the response.
Syntax
Default Value
""
Remarks
XPath may be set to navigate to specific elements within the JSON document. This will be the path to a specified value within the document. Because arrays in JSON only contain values, and no associated object name, an empty name will be used for these values. To reach an array element at position 1, the path must be set to "[1]". In addition, a root element named "json" will be added to each JSON document in the parser.
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
The XPath property accepts both XPath and JSONPath formats. Please review the following notes on both formats.
XPath
The path is a series of one or more element accessors separated by '/'. The path can be absolute (starting with '/') or relative to the current XPath location.
The following are possible values for an element accessor:
'name' | A particular element name. |
[i] | The i-th subelement of the current element. |
.. | the parent of the current element. |
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
Simple JSON Document
{ "firstlevel": { "one": "value", "two": ["first", "second"], "three": "value three" } }Example 1. Setting XPath:
Document root | JsonControl.XPath = "/" |
Specific Element | JsonControl.XPath = "/json/firstlevel/one/" |
i-th Child | JsonControl.XPath = "/json/firstlevel/two/[i]/" |
JSONPath
This property implements a subset of the JSONPath notation. This may be set to point to a specific element in the JSON document.The JSONPath is a series of one or more accessors in either dot-notation
$.store.book[0].titleor in bracket-notation, as follows:
$['store']['book'][0]['title']
After setting XPath, the following properties are populated:
Example 2. Setting JSONPath:Given the following JSON document:
{ "store": { "book": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "isbn": "0-553-21311-3", "price": 8.99 }, { "category": "fiction", "author": "J. R. R. Tolkien", "title": "The Lord of the Rings", "isbn": "0-395-19395-8", "price": 22.99 } ], "bicycle": { "color": "red", "price": 19.95 } }, }The following code shows several examples.
Get the first book's author:
json.XPath = "$.store.book[0].author";
Console.WriteLine(json.XText);
//Output
//"Nigel Rees"
Select the first book and inspect the children:
json.XPath = "$.store.book[0]";
Console.WriteLine("Child Count: " + json.XChildren.Count);
Console.WriteLine(json.XChildren[1].Name + ": " + json.XChildren[1].XText);
//Output
//Child Count: 4
//author: "Nigel Rees"
Get the price of the second book:
json.XPath = "$['store']['book'][1]['price']";
Console.WriteLine(json.XText);
//Output
//12.99
Get the second to last book's author:
json.XPath = "$['store']['book'][last() - 1]['author']";
Console.WriteLine(json.XText);
Console.WriteLine(json.XPath); //Note that "last() - 1" is resolved to "3".
//Output
//"Herman Melville"
//$['store']['book'][3]['author']
Display the full subtree at the current path:
json.XPath = "$.store.book[0]";
Console.WriteLine(json.XSubTree);
//Output
// {
// "category": "reference",
// "author": "Nigel Rees",
// "title": "Sayings of the Century",
// "price": 8.95
// }
XSubTree Property (JSON Component)
This property includes a snapshot of the current element in the document.
Syntax
Default Value
""
Remarks
The current element is specified through this property. For this property to work, you must have the CacheContent set to True.
This property is read-only.
XText Property (JSON Component)
This property includes the text of the current element.
Syntax
Default Value
""
Remarks
This property contains the text of the current element. The current element is specified through the XPath property.
Config Method (JSON Component)
Sets or retrieves a configuration setting.
Syntax
Remarks
Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.
These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.
To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).
To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.
EndArray Method (JSON Component)
This method writes the closing bracket of a JSON array.
Syntax
public void EndArray(); Async Version public async Task EndArray(); public async Task EndArray(CancellationToken cancellationToken);
Public Sub EndArray() Async Version Public Sub EndArray() As Task Public Sub EndArray(cancellationToken As CancellationToken) As Task
Remarks
This method writes the closing bracket of a JSON array to the output. An array must already have been opened by calling StartArray.
EndObject Method (JSON Component)
This method writes the closing brace of a JSON object.
Syntax
public void EndObject(); Async Version public async Task EndObject(); public async Task EndObject(CancellationToken cancellationToken);
Public Sub EndObject() Async Version Public Sub EndObject() As Task Public Sub EndObject(cancellationToken As CancellationToken) As Task
Remarks
This method writes the closing brace of a JSON object. An object must have been started previously by calling StartObject.
Flush Method (JSON Component)
This method flushes the parser's or writer's buffers.
Syntax
public void Flush(); Async Version public async Task Flush(); public async Task Flush(CancellationToken cancellationToken);
Public Sub Flush() Async Version Public Sub Flush() As Task Public Sub Flush(cancellationToken As CancellationToken) As Task
Remarks
When Flush is called, the component flushes all of its buffers, firing events as necessary.
When parsing, the end state of the JSON is checked. If Validate is also True, the parser verifies that all open elements were closed, returning an error if not.
When writing, the resultant JSON is available in one of the output properties.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
HasXPath Method (JSON Component)
This method determines whether a specific element exists in the document.
Syntax
Remarks
This method determines whether a particular XPath exists within the document. This may be used to check if a path exists before setting it through XPath.
This method returns True if the xpath exists, and False if not.
See XPath for details on the XPath syntax.
InsertProperty Method (JSON Component)
This method inserts the specified name and value at the selected position.
Syntax
public void InsertProperty(string name, string value, int valueType, int position); Async Version public async Task InsertProperty(string name, string value, int valueType, int position); public async Task InsertProperty(string name, string value, int valueType, int position, CancellationToken cancellationToken);
Public Sub InsertProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer) Async Version Public Sub InsertProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer) As Task Public Sub InsertProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer, cancellationToken As CancellationToken) As Task
Remarks
This method inserts a property and its corresponding value relative to the element specified by XPath. Before calling this method, a valid JSON document must first be loaded by calling Parse.
The Name parameter specifies the name of the property.
The Value parameter specifies the value of the property.
The ValueType parameter specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
The Position parameter specifies the position of Value relative to the element specified by XPath. Possible values are as follows:
- 0 (Before the current element)
- 1 (After the current element)
- 2 (The first child of the current element)
- 3 (The last child of the current element)
See Save for details.
InsertValue Method (JSON Component)
This method inserts the specified value at the selected position.
Syntax
public void InsertValue(string value, int valueType, int position); Async Version public async Task InsertValue(string value, int valueType, int position); public async Task InsertValue(string value, int valueType, int position, CancellationToken cancellationToken);
Public Sub InsertValue(ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer) Async Version Public Sub InsertValue(ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer) As Task Public Sub InsertValue(ByVal Value As String, ByVal ValueType As Integer, ByVal Position As Integer, cancellationToken As CancellationToken) As Task
Remarks
This method inserts a value relative to the element specified by XPath. Before calling this method, a valid JSON document must first be loaded by calling Parse.
The Value parameter specifies the value of the property.
The ValueType parameter specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
The Position parameter specifies the position of Value relative to the element specified by XPath. Possible values are as follows:
- 0 (Before the current element)
- 1 (After the current element)
- 2 (The first child of the current element)
- 3 (The last child of the current element)
See Save for details.
Parse Method (JSON Component)
This method parses the specified JSON data.
Syntax
public void Parse(); Async Version public async Task Parse(); public async Task Parse(CancellationToken cancellationToken);
Public Sub Parse() Async Version Public Sub Parse() As Task Public Sub Parse(cancellationToken As CancellationToken) As Task
Remarks
This method parses the specified JSON data.
When parsing a document, events will fire to provide information about the parsed data. After Parse returns the document, it may be navigated by setting XPath if BuildDOM is True (default). If BuildDOM is False, parsed data are accessible only through the events.
The following events will fire during parsing:
If BuildDOM is True (default), XPath may be set after this method returns. XPath may be set to navigate to specific elements within the JSON document. This will be the path to a specified value within the document. Because arrays in JSON only contain values, and no associated object name, an empty name will be used for these values. To reach an array element at position 1, the path must be set to "[1]". In addition, a root element named "json" will be added to each JSON document in the parser.
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
The XPath property accepts both XPath and JSONPath formats. Please review the following notes on both formats.
XPath
The path is a series of one or more element accessors separated by '/'. The path can be absolute (starting with '/') or relative to the current XPath location.
The following are possible values for an element accessor:
'name' | A particular element name. |
[i] | The i-th subelement of the current element. |
.. | the parent of the current element. |
BuildDOM must be set to True before parsing the document for the XPath functionality to be available.
Simple JSON Document
{ "firstlevel": { "one": "value", "two": ["first", "second"], "three": "value three" } }Example 1. Setting XPath:
Document root | JsonControl.XPath = "/" |
Specific Element | JsonControl.XPath = "/json/firstlevel/one/" |
i-th Child | JsonControl.XPath = "/json/firstlevel/two/[i]/" |
JSONPath
This property implements a subset of the JSONPath notation. This may be set to point to a specific element in the JSON document.The JSONPath is a series of one or more accessors in either dot-notation
$.store.book[0].titleor in bracket-notation, as follows:
$['store']['book'][0]['title']
After setting XPath, the following properties are populated:
Example 2. Setting JSONPath:Given the following JSON document:
{ "store": { "book": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "isbn": "0-553-21311-3", "price": 8.99 }, { "category": "fiction", "author": "J. R. R. Tolkien", "title": "The Lord of the Rings", "isbn": "0-395-19395-8", "price": 22.99 } ], "bicycle": { "color": "red", "price": 19.95 } }, }The following code shows several examples.
Get the first book's author:
json.XPath = "$.store.book[0].author";
Console.WriteLine(json.XText);
//Output
//"Nigel Rees"
Select the first book and inspect the children:
json.XPath = "$.store.book[0]";
Console.WriteLine("Child Count: " + json.XChildren.Count);
Console.WriteLine(json.XChildren[1].Name + ": " + json.XChildren[1].XText);
//Output
//Child Count: 4
//author: "Nigel Rees"
Get the price of the second book:
json.XPath = "$['store']['book'][1]['price']";
Console.WriteLine(json.XText);
//Output
//12.99
Get the second to last book's author:
json.XPath = "$['store']['book'][last() - 1]['author']";
Console.WriteLine(json.XText);
Console.WriteLine(json.XPath); //Note that "last() - 1" is resolved to "3".
//Output
//"Herman Melville"
//$['store']['book'][3]['author']
Display the full subtree at the current path:
json.XPath = "$.store.book[0]";
Console.WriteLine(json.XSubTree);
//Output
// {
// "category": "reference",
// "author": "Nigel Rees",
// "title": "Sayings of the Century",
// "price": 8.95
// }
Input Properties
The component will determine the source of the input based on which properties are set.
The order in which the input properties are checked is as follows:
When a valid source is found, the search stops.If parsing multiple documents, call Reset between documents to reset the parser.
PutName Method (JSON Component)
This method writes the name of a property.
Syntax
public void PutName(string name); Async Version public async Task PutName(string name); public async Task PutName(string name, CancellationToken cancellationToken);
Public Sub PutName(ByVal Name As String) Async Version Public Sub PutName(ByVal Name As String) As Task Public Sub PutName(ByVal Name As String, cancellationToken As CancellationToken) As Task
Remarks
This method writes the name of a property. The Name parameter specifies the value to write.
PutProperty Method (JSON Component)
This method writes a property and value.
Syntax
public void PutProperty(string name, string value, int valueType); Async Version public async Task PutProperty(string name, string value, int valueType); public async Task PutProperty(string name, string value, int valueType, CancellationToken cancellationToken);
Public Sub PutProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer) Async Version Public Sub PutProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer) As Task Public Sub PutProperty(ByVal Name As String, ByVal Value As String, ByVal ValueType As Integer, cancellationToken As CancellationToken) As Task
Remarks
This method writes a property and its corresponding value to the output.
The Name parameter specifies the name of the property.
The Value parameter specifies the value of the property.
The ValueType parameter specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
PutRaw Method (JSON Component)
This method writes a raw JSON fragment.
Syntax
public void PutRaw(string text); Async Version public async Task PutRaw(string text); public async Task PutRaw(string text, CancellationToken cancellationToken);
Public Sub PutRaw(ByVal Text As String) Async Version Public Sub PutRaw(ByVal Text As String) As Task Public Sub PutRaw(ByVal Text As String, cancellationToken As CancellationToken) As Task
Remarks
This method writes raw data to the output. This may be used to write any data of any format directly to the output.
PutValue Method (JSON Component)
This method writes a value of a property.
Syntax
Remarks
This method writes the value of a property to the output. The Value parameter specifies the value. The ValueType parameter specifies the type of data. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
Remove Method (JSON Component)
This method removes the element or value set in XPath.
Syntax
public void Remove(); Async Version public async Task Remove(); public async Task Remove(CancellationToken cancellationToken);
Public Sub Remove() Async Version Public Sub Remove() As Task Public Sub Remove(cancellationToken As CancellationToken) As Task
Remarks
This method removes the current object at the specified XPath. This is used when editing previously loaded JSON documents.
See Save for details.
Reset Method (JSON Component)
This method resets the component
Syntax
public void Reset(); Async Version public async Task Reset(); public async Task Reset(CancellationToken cancellationToken);
Public Sub Reset() Async Version Public Sub Reset() As Task Public Sub Reset(cancellationToken As CancellationToken) As Task
Remarks
This method resets the JSON parser.
Save Method (JSON Component)
This method saves the modified JSON document.
Syntax
public void Save(); Async Version public async Task Save(); public async Task Save(CancellationToken cancellationToken);
Public Sub Save() Async Version Public Sub Save() As Task Public Sub Save(cancellationToken As CancellationToken) As Task
Remarks
This method saves the modified JSON data. This is used after editing a previously loaded JSON document.
After loading a JSON document with Parse the document may be edited. The component supports inserting new values, renaming or overwriting existing values, and removing values. After editing is complete, call Save to output the updated JSON document.
The following methods are applicable when modifying a JSON document:
When Save is called, the modified JSON is written to the specified output location.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
Example 1. Inserting New Values:
To insert new values in a JSON document, first load the existing document with Parse. Next set XPath to the sibling or parent of the data to be inserted. Call InsertProperty or InsertValue and pass the ValueType and Position parameters to indicate the type of data being inserted and the position.
The ValueType parameter of these methods specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
The Position parameter of these methods specifies the position of Value. Possible values are as follows:
- 0 (Before the current element)
- 1 (After the current element)
- 2 (The first child of the current element)
- 3 (The last child of the current element)
For example:
Given the following JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", } ] } }
Insert a new property "price" for each book:
json.XPath = "/json/store/books/[1]";
json.InsertProperty("price", "8.95", 3, 3); //3 - Number, 3 - Last Child
json.XPath = "/json/store/books/[2]";
json.InsertProperty("price", "12.99", 3, 3); //3 - Number, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 } ] } }
To add a new book to the array:
json.XPath = "/json/store/books";
json.InsertValue("", 0, 3); //0 - Object, 3 - Last Child
json.XPath = "/json/store/books/[3]";
json.InsertProperty("category", "fiction", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("author", "Herman Melville", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("title", "Moby Dick", 2, 3); //2 - String, 3 - Last Child
json.InsertProperty("price", "8.99", 3, 3); //3 - Number, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
To add a new array property to each book:
json.XPath = "/json/store/books/[1]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[1]/tags";
json.InsertValue("quotes", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("british", 2, 3); //2 - String, 3 - Last Child
json.XPath = "/json/store/books/[2]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[2]/tags";
json.InsertValue("trilogy", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("war", 2, 3); //2 - String, 3 - Last Child
json.XPath = "/json/store/books/[3]";
json.InsertProperty("tags", "", 1, 2); //1 - Array, 2 - First Child
json.XPath = "/json/store/books/[3]/tags";
json.InsertValue("classic", 2, 3); //2 - String, 3 - Last Child
json.InsertValue("whales", 2, 3); //2 - String, 3 - Last Child
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["quotes", "british"], "category": "reference", "author": "Nigel Rees", "title": "Sayings of the Century", "price": 8.95 }, { "tags": ["trilogy", "war"], "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
Example 2. Removing Values:
To remove existing values, set XPath and call the Remove method. Continuing with example 1, to remove
the first book:
json.XPath = "/json/store/books/[1]";
json.Remove();
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["trilogy", "war"], "category": "fiction", "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
To remove the "category" properties from each book:
json.XPath = "/json/store/books/[1]/category";
json.Remove();
json.XPath = "/json/store/books/[2]/category";
json.Remove();
json.Save();
Produces the JSON:
{ "store": { "books": [ { "tags": ["trilogy", "war"], "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 12.99 }, { "tags": ["classic", "whales"], "author": "Herman Melville", "title": "Moby Dick", "price": 8.99 } ] } }
Example 3. Updating Existing Names and Values:
The SetName and SetValue methods may be used to modify existing names and values. Continuing with the preceding JSON in example 2, to rename "tags" to "meta" and update values within the array and prices:
//Rename "tags" to "meta" for 1st book
json.XPath = "/json/store/books/[1]/tags";
json.SetName("meta");
//Update Price
json.XPath = "/json/store/books/[1]/price";
json.SetValue("13.99", 3); //3 - Number
//Rename "tags" to "meta" for 2nd book
json.XPath = "/json/store/books/[2]/tags";
json.SetName("meta");
//Update tag "whales" to "revenge"
json.XPath = "/json/store/books/[2]/meta/[2]";
json.SetValue("revenge", 2); //2 - String
//Update Price
json.XPath = "/json/store/books/[2]/price";
json.SetValue("9.99", 3); //3 - Number
json.Save();
Produces the JSON:
{ "store": { "books": [ { "meta": ["trilogy", "war"], "author": "Evelyn Waugh", "title": "Sword of Honour", "price": 13.99 }, { "meta": ["classic", "revenge"], "author": "Herman Melville", "title": "Moby Dick", "price": 9.99 } ] } }
SetInputStream Method (JSON Component)
This method sets the stream from which the component will read data to parse.
Syntax
public void SetInputStream(System.IO.Stream inputStream); Async Version public async Task SetInputStream(System.IO.Stream inputStream); public async Task SetInputStream(System.IO.Stream inputStream, CancellationToken cancellationToken);
Public Sub SetInputStream(ByVal InputStream As System.IO.Stream) Async Version Public Sub SetInputStream(ByVal InputStream As System.IO.Stream) As Task Public Sub SetInputStream(ByVal InputStream As System.IO.Stream, cancellationToken As CancellationToken) As Task
Remarks
This method specifies a stream from which data will be read when Parse is called.
Input Properties
The component will determine the source of the input based on which properties are set.
The order in which the input properties are checked is as follows:
When a valid source is found, the search stops.SetName Method (JSON Component)
This method sets a new name for the element specified by XPath.
Syntax
public void SetName(string name); Async Version public async Task SetName(string name); public async Task SetName(string name, CancellationToken cancellationToken);
Public Sub SetName(ByVal Name As String) Async Version Public Sub SetName(ByVal Name As String) As Task Public Sub SetName(ByVal Name As String, cancellationToken As CancellationToken) As Task
Remarks
This method sets a new name for the element specified in XPath. This is used to modify an existing JSON document.
The Name parameter specifies the new name of the element.
See Save for details.
SetOutputStream Method (JSON Component)
This method sets the stream to which the component will write the JSON.
Syntax
public void SetOutputStream(System.IO.Stream outputStream); Async Version public async Task SetOutputStream(System.IO.Stream outputStream); public async Task SetOutputStream(System.IO.Stream outputStream, CancellationToken cancellationToken);
Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream) Async Version Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream) As Task Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream, cancellationToken As CancellationToken) As Task
Remarks
This method sets the stream to which the output will be written when writing data.
Output Properties
The component will determine the destination of the output based on which properties are set.
The order in which the output properties are checked is as follows:
- SetOutputStream
- OutputFile
- OutputData: The output data are written to this property if no other destination is specified.
SetValue Method (JSON Component)
This method sets a new value for the element specified by XPath.
Syntax
Remarks
This method sets a new value for the element specified in XPath. This is used to modify an existing JSON document.
Value specifies the new value.
ValueType specifies the type of the value. Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
See Save for details.
StartArray Method (JSON Component)
This method writes the opening bracket of a JSON array.
Syntax
public void StartArray(); Async Version public async Task StartArray(); public async Task StartArray(CancellationToken cancellationToken);
Public Sub StartArray() Async Version Public Sub StartArray() As Task Public Sub StartArray(cancellationToken As CancellationToken) As Task
Remarks
This method writes the opening bracket of a JSON array to the output. To close the array, call EndArray.
StartObject Method (JSON Component)
This event writes the opening brace of a JSON object.
Syntax
public void StartObject(); Async Version public async Task StartObject(); public async Task StartObject(CancellationToken cancellationToken);
Public Sub StartObject() Async Version Public Sub StartObject() As Task Public Sub StartObject(cancellationToken As CancellationToken) As Task
Remarks
This method writes the opening brace of a JSON object to the output. To close the object, call EndObject.
TryXPath Method (JSON Component)
This method navigates to the specified XPath if it exists.
Syntax
Remarks
This method will attempt to navigate to the specified XPath parameter if it exists within the document.
If the XPath exists, the XPath property will be updated and this method returns True.
If the XPath does not exist, the XPath property is not updated and this method returns False.
Characters Event (JSON Component)
This event is fired for plaintext segments of the input stream.
Syntax
public event OnCharactersHandler OnCharacters; public delegate void OnCharactersHandler(object sender, JSONCharactersEventArgs e); public class JSONCharactersEventArgs : EventArgs { public string Text { get; } }
Public Event OnCharacters As OnCharactersHandler Public Delegate Sub OnCharactersHandler(sender As Object, e As JSONCharactersEventArgs) Public Class JSONCharactersEventArgs Inherits EventArgs Public ReadOnly Property Text As String End Class
Remarks
The Characters event provides the plaintext content of the JSON document (i.e., the text inside the elements). The text is provided through the Text parameter.
The text includes white space as well as end-of-line characters, except for ignorable whitespace, which is fired through the IgnorableWhitespace event.
EndDocument Event (JSON Component)
This event fires when the end of a JSON document is encountered.
Syntax
public event OnEndDocumentHandler OnEndDocument; public delegate void OnEndDocumentHandler(object sender, JSONEndDocumentEventArgs e); public class JSONEndDocumentEventArgs : EventArgs { }
Public Event OnEndDocument As OnEndDocumentHandler Public Delegate Sub OnEndDocumentHandler(sender As Object, e As JSONEndDocumentEventArgs) Public Class JSONEndDocumentEventArgs Inherits EventArgs End Class
Remarks
This event fires when parsing of a JSON document ends. This event may fire multiple times if InputFormat is set to a value that accepts multiple JSON documents.
EndElement Event (JSON Component)
This event is fired when an end-element tag is encountered.
Syntax
public event OnEndElementHandler OnEndElement; public delegate void OnEndElementHandler(object sender, JSONEndElementEventArgs e); public class JSONEndElementEventArgs : EventArgs { public string Element { get; } }
Public Event OnEndElement As OnEndElementHandler Public Delegate Sub OnEndElementHandler(sender As Object, e As JSONEndElementEventArgs) Public Class JSONEndElementEventArgs Inherits EventArgs Public ReadOnly Property Element As String End Class
Remarks
The EndElement event is fired when the end of an element is found in the document.
The element name is provided by the Element parameter.
Error Event (JSON Component)
Fired when information is available about errors during data delivery.
Syntax
public event OnErrorHandler OnError; public delegate void OnErrorHandler(object sender, JSONErrorEventArgs e); public class JSONErrorEventArgs : EventArgs { public int ErrorCode { get; } public string Description { get; } }
Public Event OnError As OnErrorHandler Public Delegate Sub OnErrorHandler(sender As Object, e As JSONErrorEventArgs) Public Class JSONErrorEventArgs Inherits EventArgs Public ReadOnly Property ErrorCode As Integer Public ReadOnly Property Description As String End Class
Remarks
The Error event is fired in case of exceptional conditions during message processing. Normally the component throws an exception.
The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.
IgnorableWhitespace Event (JSON Component)
This event is fired when a section of ignorable whitespace is encountered.
Syntax
public event OnIgnorableWhitespaceHandler OnIgnorableWhitespace; public delegate void OnIgnorableWhitespaceHandler(object sender, JSONIgnorableWhitespaceEventArgs e); public class JSONIgnorableWhitespaceEventArgs : EventArgs { public string Text { get; } }
Public Event OnIgnorableWhitespace As OnIgnorableWhitespaceHandler Public Delegate Sub OnIgnorableWhitespaceHandler(sender As Object, e As JSONIgnorableWhitespaceEventArgs) Public Class JSONIgnorableWhitespaceEventArgs Inherits EventArgs Public ReadOnly Property Text As String End Class
Remarks
The ignorable whitespace section is provided by the Text parameter.
JSON Event (JSON Component)
This event fires with the JSON data being written.
Syntax
public event OnJSONHandler OnJSON; public delegate void OnJSONHandler(object sender, JSONJSONEventArgs e); public class JSONJSONEventArgs : EventArgs { public string Text { get; } }
Public Event OnJSON As OnJSONHandler Public Delegate Sub OnJSONHandler(sender As Object, e As JSONJSONEventArgs) Public Class JSONJSONEventArgs Inherits EventArgs Public ReadOnly Property Text As String End Class
Remarks
This event fires when output data are written.
Text contains the JSON data currently being written.
StartDocument Event (JSON Component)
This event fires when the start of a new JSON document is encountered.
Syntax
public event OnStartDocumentHandler OnStartDocument; public delegate void OnStartDocumentHandler(object sender, JSONStartDocumentEventArgs e); public class JSONStartDocumentEventArgs : EventArgs { }
Public Event OnStartDocument As OnStartDocumentHandler Public Delegate Sub OnStartDocumentHandler(sender As Object, e As JSONStartDocumentEventArgs) Public Class JSONStartDocumentEventArgs Inherits EventArgs End Class
Remarks
This event fires when parsing of a JSON document begins. This event may fire multiple times if InputFormat is set to a value that accepts multiple JSON documents.
StartElement Event (JSON Component)
This event is fired when a new element is encountered in the document.
Syntax
public event OnStartElementHandler OnStartElement; public delegate void OnStartElementHandler(object sender, JSONStartElementEventArgs e); public class JSONStartElementEventArgs : EventArgs { public string Element { get; } }
Public Event OnStartElement As OnStartElementHandler Public Delegate Sub OnStartElementHandler(sender As Object, e As JSONStartElementEventArgs) Public Class JSONStartElementEventArgs Inherits EventArgs Public ReadOnly Property Element As String End Class
Remarks
The StartElement event is fired when a new element is found in the document.
The element name is provided through the Element parameter.
JSONElement Type
This type describes an element contained within the JSON document.
Remarks
This type describes a JSON element.
The elements are inserted into the array in the same order they are found in the document.
Fields
ElementType
TXElementTypes (read-only)
Default: 0
The ElementType field indicates the data type of the element.
Possible values are as follows:
- 0 (Object)
- 1 (Array)
- 2 (String)
- 3 (Number)
- 4 (Bool)
- 5 (Null)
- 6 (Raw)
Name
string (read-only)
Default: ""
The Name field provides the name of the element. For elements within an array, the Name field will be empty.
XText
string (read-only)
Default: ""
This field contains the text of the element.
Constructors
public JSONElement();
Public JSONElement()
Config Settings (JSON Component)
The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.JSON Config Settings
string elementXPath = json.Config("ElementXPath");
Note: The BuildDOM property must be set to False.
Value | Description |
0 (None - default) | Only a single JSON document is expected. Use this when a single JSON document is being parsed (most cases). |
1 (Line Delimited) | Multiple documents are separated by carriage return (CR), line feed (LF), or CRLF character sequences. |
2 (Record Separated) | A defined start and end delimiter separate documents. See RecordStartDelimiter and RecordEndDelimiter. |
3 (Concatenated) | New documents begin immediately after the previous documents end; no characters or delimiters separate the documents. |
json.Config("PrettyPrint=true"); // false
json.StartObject();
json.PutName("data");
json.StartObject();
json.PutProperty("id", "3", 3);
json.PutProperty("first_name", "Emma", 2);
json.PutProperty("last_name", "Wong", 2);
json.PutProperty("avatar", "https://s3.amazonaws.com/uifaces/faces/twitter/olegpogodaev/128.jpg", 2);
json.EndObject();
json.EndObject();
json.Flush();
Console.WriteLine(json.OutputData);
With PrettyPrint set to False (the default), the output would look like this:
{"data":{"id":3,"first_name":"Emma","last_name":"Wong","avatar":"https:\/\/s3.amazonaws.com\/uifaces\/faces\/twitter\/olegpogodaev\/128.jpg"}}With PrettyPrint set to True, the output instead would look like this:
{ "data": { "id": 3, "first_name": "Emma", "last_name": "Wong", "avatar": "https:\/\/s3.amazonaws.com\/uifaces\/faces\/twitter\/olegpogodaev\/128.jpg" } }The default value is False.
0 (none - default) | No additional processing is performed. |
1 (unquote) | Strings are unquoted. |
2 (unescape) | Any escaped sequences are unescaped. |
3 (unquote and unescape) | Values are both unquoted and unescaped. |
"example" : "value\ntest"The following table shows the resulting value for the XText of the element:
StringProcessingOption | Output |
0 (none) | "value\ntest" |
1 (unquote) | value\ntest |
2 (unescape) | "value test" |
3 (unquote and unescape) | value test |
- 0 (Auto - default)
- 1 (XPath)
- 2 (JSONPath)
Base Config Settings
In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the component does not attempt to process external events.
- Product: The product the license is for.
- Product Key: The key the license was generated from.
- License Source: Where the license was found (e.g., RuntimeLicense, License File).
- License Type: The type of license installed (e.g., Royalty Free, Single Server).
- Last Valid Build: The last valid build number for which the license will work.
This setting only works on these components: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.
Setting this configuration setting to true tells the component to use the internal implementation instead of using the system security libraries.
On Windows, this setting is set to false by default. On Linux/macOS, this setting is set to true by default.
If using the .NET Standard Library, this setting will be true on all platforms. The .NET Standard library does not support using the system security libraries.
Note: This setting is static. The value set is applicable to all components used in the application.
When this value is set, the product's system dynamic link library (DLL) is no longer required as a reference, as all unmanaged code is stored in that file.
Trappable Errors (JSON Component)
JSON Errors
10231 | Unbalanced element tag. |
10232 | Invalid JSON markup. |
10233 | Invalid XPath. |
10234 | DOM tree unavailable (set BuildDOM to True and reparse). |
XML Errors
101 | Invalid attribute index. |
102 | No attributes available. |
103 | Invalid namespace index. |
104 | No namespaces available. |
105 | Invalid element index. |
106 | No elements available. |
107 | Attribute does not exist. |
201 | Unbalanced element tag. |
202 | Unknown element prefix (cannot find namespace). |
203 | Unknown attribute prefix (cannot find namespace). |
204 | Invalid XML markup. |
205 | Invalid end state for parser. |
206 | Document contains unbalanced elements. |
207 | Invalid XPath. |
208 | No such child. |
209 | Top element does not match start of path. |
210 | DOM tree unavailable (set BuildDOM to True and reparse). |
302 | Cannot open file. |
401 | Invalid XML would be generated. |
402 | An invalid XML name has been specified. |