XML Component

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The XML component can be used to both parse and create XML documents.

Syntax

TipwXML

Remarks

The XML component can operate as either a parser or writer of XML.

Parsing XML

The XML component parses XML documents and verifies that they are well formed. The results are provided through a set of events complying with the SAX2 specification.

In addition, the document structure may be queried through an XPath mechanism that supports a subset of the XPath specification.

The parser is optimized for read applications, with a very fast engine that builds internal Document Object Model (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 may be navigated by setting XPath if BuildDOM is True (default). If BuildDOM is False, parsed data are accessible only through the events.

Events are fired only when qualifying conditions (e.g., the beginning of a new element) are met. In the meantime, text will be buffered internally. The following events will fire during parsing:

• Characters
• Comment
• EndElement
• EndPrefixMapping
• EvalEntity
• IgnorableWhitespace
• Meta
• PI
• SpecialSection
• StartElement
• StartPrefixMapping

If BuildDOM is True (default), XPath may be set after this method returns. XPath implements a subset of the XML XPath specification, allowing you to point to specific elements in the XML documents.

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:

BuildDOM must be set to True before parsing the document for the XPath functionality to be available.

Example. Setting XPath:

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:

• InputFile
• InputData

If parsing multiple documents, call Reset between documents to reset the parser.

An additional "relaxed" mode allows for lexical parsing of non-XML documents (e.g., HTML). This is enabled by setting Validate to False. In this case, events will be fired as elements, entities, and so on are encountered, but the structure of the document will not be checked for "well-formedness", and the internal DOM structure will not be built.

Writing XML

To use the component, first decide whether or not to write to file, or to OutputData.

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:

• OutputFile
• OutputData: The output data are written to this property if no other destination is specified.

To begin writing the XML document, first optionally set XMLDeclaration. If this is not set, the component will use a default XML declaration at the beginning of the document.

Next, begin adding elements to your document. Calling StartElement will open an element with the specified name. To create a nested structure, continue calling StartElement to open more child elements. To write a value within an element, call PutString. To close the element that was last opened, call EndElement. Each time EndElement is called, the element at the current level is closed. Alternatively, calling PutElement will write the element specified with the value specified and will also close the element.

To write an attribute of the current element, after calling StartElement call PutAttr. Call PutAttr multiple times to add multiple attributes.

Writing comments or CDATA can be done at any time with the PutComment and PutCData methods.

To close your XML document, call Save. You can call Save from any location, and it will close any remaining open elements automatically.

Property List

The following is the full list of the properties of the component with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the component with short descriptions. Click on the links for further details.

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.

Config Settings

The following is a list of config settings for the component with short descriptions. Click on the links for further details.

BuildDOM Property (XML Component)

When set to True, this property creates an internal object model of the XML document.

Syntax

__property bool BuildDOM = { read=FBuildDOM, write=FSetBuildDOM };

Default Value

true

Remarks

Set BuildDOM to True when you need to browse the current document through XPath.

Validate is automatically set to True when BuildDOM is set to True.

Data Type

Boolean

InputData Property (XML Component)

This property specifies the XML data to parse.

Syntax

__property String InputData = { read=FInputData, write=FSetInputData };

Default Value

""

Remarks

This property specifies the XML to be processed. Set this property before calling Parse.

This property may be set to a complete XML document or to partial data. When setting partial data, call Parse after each chunk of data is set. For instance:

//Parse the following in chunks: <test>1</test> xml.InputData = "<test>" xml.Parse(); xml.InputData = "1<test>" xml.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:

• InputFile
• InputData

Data Type

String

InputFile Property (XML Component)

This property specifies the file to process.

Syntax

__property String InputFile = { read=FInputFile, write=FSetInputFile };

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:

• InputFile
• InputData

Data Type

String

NamespaceCount Property (XML Component)

The number of records in the Namespace arrays.

Syntax

__property int NamespaceCount = { read=FNamespaceCount, write=FSetNamespaceCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• NamespacePrefix
• NamespaceURI

The array indices start at 0 and end at NamespaceCount - 1.

This property is not available at design time.

Data Type

Integer

NamespacePrefix Property (XML Component)

This property contains the Prefix for the Namespace .

Syntax

__property String NamespacePrefix[int NamespaceIndex] = { read=FNamespacePrefix, write=FSetNamespacePrefix };

Default Value

""

Remarks

This property contains the NamespacePrefix for the Namespace.

The NamespaceIndex parameter specifies the index of the item in the array. The size of the array is controlled by the NamespaceCount property.

This property is not available at design time.

Data Type

String

NamespaceURI Property (XML Component)

This property contains the namespace URI associated with the corresponding Prefix .

Syntax

__property String NamespaceURI[int NamespaceIndex] = { read=FNamespaceURI, write=FSetNamespaceURI };

Default Value

""

Remarks

This property contains the namespace URI associated with the corresponding NamespacePrefix. This URL is usually pointing to the XML schema for the namespace.

The NamespaceIndex parameter specifies the index of the item in the array. The size of the array is controlled by the NamespaceCount property.

This property is not available at design time.

Data Type

String

OutputData Property (XML Component)

The output XML after processing.

Syntax

__property String OutputData = { read=FOutputData, write=FSetOutputData };

Default Value

""

Remarks

This property will be populated with the output from the operation if OutputFile is not set.

Data Type

String

OutputFile Property (XML Component)

This property includes the path to a local file where the output will be written.

Syntax

__property String OutputFile = { read=FOutputFile, write=FSetOutputFile };

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:

• OutputFile
• OutputData: The output data are written to this property if no other destination is specified.

Data Type

String

Overwrite Property (XML Component)

This property indicates whether or not the component should overwrite files.

Syntax

__property bool Overwrite = { read=FOverwrite, write=FSetOverwrite };

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.

Data Type

Boolean

Validate Property (XML Component)

This property controls whether documents are validated during parsing.

Syntax

__property bool Validate = { read=FValidate, write=FSetValidate };

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.

Data Type

Boolean

AttrCount Property (XML Component)

The number of records in the Attr arrays.

Syntax

__property int AttrCount = { read=FAttrCount, write=FSetAttrCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• AttrName
• AttrNamespace
• AttrPrefix
• AttrValue

The array indices start at 0 and end at AttrCount - 1.

This property is not available at design time.

Data Type

Integer

AttrName Property (XML Component)

The Name provides the local name (without prefix) of the attribute.

Syntax

__property String AttrName[int AttrIndex] = { read=FAttrName };

Default Value

""

Remarks

The AttrName provides the local name (without prefix) of the attribute.

The AttrIndex parameter specifies the index of the item in the array. The size of the array is controlled by the AttrCount property.

This property is read-only and not available at design time.

Data Type

String

AttrNamespace Property (XML Component)

This property contains the attribute namespace.

Syntax

__property String AttrNamespace[int AttrIndex] = { read=FAttrNamespace };

Default Value

""

Remarks

This property contains the attribute namespace.

The AttrIndex parameter specifies the index of the item in the array. The size of the array is controlled by the AttrCount property.

This property is read-only and not available at design time.

Data Type

String

AttrPrefix Property (XML Component)

This property contains the attribute prefix (if any).

Syntax

__property String AttrPrefix[int AttrIndex] = { read=FAttrPrefix };

Default Value

""

Remarks

This property contains the attribute prefix (if any). If the attribute does not have a prefix, this property is empty.

The AttrIndex parameter specifies the index of the item in the array. The size of the array is controlled by the AttrCount property.

This property is read-only and not available at design time.

Data Type

String

AttrValue Property (XML Component)

This property contains the attribute value.

Syntax

__property String AttrValue[int AttrIndex] = { read=FAttrValue };

Default Value

""

Remarks

This property contains the attribute value.

The AttrIndex parameter specifies the index of the item in the array. The size of the array is controlled by the AttrCount property.

This property is read-only and not available at design time.

Data Type

String

XChildCount Property (XML Component)

The number of records in the XChild arrays.

Syntax

__property int XChildCount = { read=FXChildCount, write=FSetXChildCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• XChildName
• XChildNamespace
• XChildPrefix
• XChildXText

The array indices start at 0 and end at XChildCount - 1.

This property is not available at design time.

Data Type

Integer

XChildName Property (XML Component)

The Name property provides the local name (without a prefix) of the element.

Syntax

__property String XChildName[int XChildIndex] = { read=FXChildName };

Default Value

""

Remarks

The XChildName property provides the local name (without a prefix) of the element.

The XChildIndex parameter specifies the index of the item in the array. The size of the array is controlled by the XChildCount property.

This property is read-only and not available at design time.

Data Type

String

XChildNamespace Property (XML Component)

This property contains the namespace of the element.

Syntax

__property String XChildNamespace[int XChildIndex] = { read=FXChildNamespace };

Default Value

""

Remarks

This property contains the namespace of the element.

The XChildIndex parameter specifies the index of the item in the array. The size of the array is controlled by the XChildCount property.

This property is read-only and not available at design time.

Data Type

String

XChildPrefix Property (XML Component)

This property contains the prefix of the element (if any).

Syntax

__property String XChildPrefix[int XChildIndex] = { read=FXChildPrefix };

Default Value

""

Remarks

This property contains the prefix of the element (if any). If the element does not have a prefix, this property is empty.

The XChildIndex parameter specifies the index of the item in the array. The size of the array is controlled by the XChildCount property.

This property is read-only and not available at design time.

Data Type

String

XChildXText Property (XML Component)

This property contains the inner text of the element.

Syntax

__property String XChildXText[int XChildIndex] = { read=FXChildXText };

Default Value

""

Remarks

This property contains the inner text of the element.

The XChildIndex parameter specifies the index of the item in the array. The size of the array is controlled by the XChildCount property.

This property is read-only and not available at design time.

Data Type

String

XCommentCount Property (XML Component)

The number of records in the XComment arrays.

Syntax

__property int XCommentCount = { read=FXCommentCount, write=FSetXCommentCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• XCommentText

The array indices start at 0 and end at XCommentCount - 1.

This property is not available at design time.

Data Type

Integer

XCommentText Property (XML Component)

This property holds the comment text.

Syntax

__property String XCommentText[int XCommentIndex] = { read=FXCommentText, write=FSetXCommentText };

Default Value

""

Remarks

This property holds the comment text.

The XCommentIndex parameter specifies the index of the item in the array. The size of the array is controlled by the XCommentCount property.

This property is not available at design time.

Data Type

String

XElement Property (XML Component)

This property includes the name of the current element.

Syntax

__property String XElement = { read=FXElement, write=FSetXElement };

Default Value

""

Remarks

The current element is specified through the XPath property.

Data Type

String

XMLDeclarationEncoding Property (XML Component)

This property specifies the XML encoding to use.

Syntax

__property String XMLDeclarationEncoding = { read=FXMLDeclarationEncoding, write=FSetXMLDeclarationEncoding };

Default Value

"utf-8"

Remarks

This property specifies the XML encoding to use.

This may be set before writing a document. The default value is UTF-8.

This is applicable only when writing XML.

This property is not available at design time.

Data Type

String

XMLDeclarationStandalone Property (XML Component)

This property indicates whether the standalone attribute is present in the declaration with a value of True.

Syntax

__property bool XMLDeclarationStandalone = { read=FXMLDeclarationStandalone, write=FSetXMLDeclarationStandalone };

Default Value

true

Remarks

This property indicates whether the standalone attribute is present in the declaration with a value of True.

This may be set before writing a document. The default value is True.

This is applicable only when writing XML.

This property is not available at design time.

Data Type

Boolean

XMLDeclarationVersion Property (XML Component)

This property specifies the XML version.

Syntax

__property String XMLDeclarationVersion = { read=FXMLDeclarationVersion, write=FSetXMLDeclarationVersion };

Default Value

"1.0"

Remarks

This property specifies the XML version.

This may be set before writing a document. The default value is 1.0.

This is applicable only when writing XML.

This property is not available at design time.

Data Type

String

XNamespace Property (XML Component)

This property includes the namespace of the current element.

Syntax

__property String XNamespace = { read=FXNamespace, write=FSetXNamespace };

Default Value

""

Remarks

The current element is specified through the XPath property.

Data Type

String

XParent Property (XML Component)

This property includes the parent of the current element.

Syntax

__property String XParent = { read=FXParent };

Default Value

""

Remarks

The current element is specified through the XPath property.

This property is read-only.

Data Type

String

XPath Property (XML Component)

This property provides a way to point to a specific element in the document.

Syntax

__property String XPath = { read=FXPath, write=FSetXPath };

Default Value

""

Remarks

XPath implements a subset of the XML XPath specification, allowing you to point to specific elements in the XML documents.

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:

BuildDOM must be set to True before parsing the document for the XPath functionality to be available.

Example. Setting XPath:

Data Type

String

XPrefix Property (XML Component)

This property includes the prefix of the current element.

Syntax

__property String XPrefix = { read=FXPrefix, write=FSetXPrefix };

Default Value

""

Remarks

The current element is specified through the XPath property.

Data Type

String

XSubTree Property (XML Component)

This property includes a snapshot of the current element in the document.

Syntax

__property String XSubTree = { read=FXSubTree };

Default Value

""

Remarks

The current element is specified through the XPath property. For this property to work, you must set the CacheContent to True.

This property is read-only.

Data Type

String

XText Property (XML Component)

This property includes the text of the current element.

Syntax

__property String XText = { read=FXText, write=FSetXText };

Default Value

""

Remarks

The current element is specified through the XPath property.

Data Type

String

Config Method (XML Component)

Sets or retrieves a configuration setting.

Syntax

String __fastcall Config(String ConfigurationString);

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.

EndElement Method (XML Component)

This method writes the closing tag of an open XML element.

Syntax

void __fastcall EndElement();

Remarks

This method writes the closing tag of the XML element most recently opened using StartElement.

If no elements are opened, the call raises an exception

Flush Method (XML Component)

This method flushes the parser and checks its end state.

Syntax

void __fastcall Flush();

Remarks

When Flush is called, the parser flushes all its buffers, firing events as necessary, and then checks its end state. If Validate is True, the parser verifies that all open elements were closed, returning an error if not.

GetAttr Method (XML Component)

This method returns the value of the specified attribute.

Syntax

String __fastcall GetAttr(String AttrName);

Remarks

This method returns the value of the attribute specified by the AttrName parameter.

If the attribute does not exist, an empty string is returned. The behavior when an attribute does not exit is controlled by ErrorOnEmptyAttr.

Please refer to the AttrName, AttrNamespace, AttrPrefix, and AttrValue properties for more information.

HasXPath Method (XML Component)

This method determines whether a specific element exists in the document.

Syntax

bool __fastcall HasXPath(String XPath);

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.

LoadDOM Method (XML Component)

This method loads the document object model (DOM) from a file.

Syntax

void __fastcall LoadDOM(String FileName);

Remarks

The LoadDOM method loads a DOM structure previously saved by SaveDOM from the file specified in FileName.

Please refer to the SaveDOM method for more information.

LoadSchema Method (XML Component)

This method loads the XML schema.

Syntax

void __fastcall LoadSchema(String Schema);

Remarks

This functionality is not yet implemented.

This method loads the schema specified in the Schema parameter. The Schema may be specified as either a string or the path to a file on disk.

The component will validate the input data during parsing to verify whether or not it adheres to the schema.

Parse Method (XML Component)

This method parses the specified XML data.

Syntax

void __fastcall Parse();

Remarks

This method parses the specified XML data.

When parsing a document, events will fire to provide information about the parsed data. After Parse returns, the document may be navigated by setting XPath if BuildDOM is True (default). If BuildDOM is False, parsed data are accessible only through the events.

Events are fired only when qualifying conditions (e.g., the beginning of a new element) are met. In the meantime, text will be buffered internally. The following events will fire during parsing:

• Characters
• Comment
• EndElement
• EndPrefixMapping
• EvalEntity
• IgnorableWhitespace
• Meta
• PI
• SpecialSection
• StartElement
• StartPrefixMapping

If BuildDOM is True (default), XPath may be set after this method returns. XPath implements a subset of the XML XPath specification, allowing you to point to specific elements in the XML documents.

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:

BuildDOM must be set to True before parsing the document for the XPath functionality to be available.

Example. Setting XPath:

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:

• InputFile
• InputData

If parsing multiple documents, call Reset between documents to reset the parser.

PutAttr Method (XML Component)

This method writes an XML attribute.

Syntax

void __fastcall PutAttr(String Name, String NamespaceURI, String Value);

Remarks

This method writes an XML attribute on the currently opened XML element. It must be called right after calling StartElement and before any calls to PutString, PutComment, or PutRaw.

If Name is a local name without a prefix, the component will automatically introduce a new xmlns="NamespaceURI" attribute, if necessary.

If Name is in the form prefix:local, then component will automatically introduce a new xmlns:prefix="NamespaceURI" as necessary.

Certain attribute names will be handled in special ways by this method. If Name is "xmlns" or uses the "xmlns" prefix, the attribute will be interpreted as a namespace declaration, regardless of the value of NamespaceURI. Similarly, any attribute using the "xml" prefix will be interpreted as a special attribute (like "xml:lang") and NamespaceURI will be ignored.

PutCData Method (XML Component)

This method writes an XML CDATA block.

Syntax

void __fastcall PutCData(String Text);

Remarks

This methods writes a new XML CDATA block with the specified text inside the current element.

PutComment Method (XML Component)

This method writes an XML comment block.

Syntax

void __fastcall PutComment(String Text);

Remarks

This method writes a new XML comment block with the specified text.

PutElement Method (XML Component)

This method writes a simple XML element with a value.

Syntax

void __fastcall PutElement(String Name, String NamespaceURI, String Value);

Remarks

This method writes a simple XML element with no attributes and the specified value between the opening and closing tags.

If Name is a local name without a prefix, the component will automatically introduce a new xmlns="NamespaceURI" attribute, if necessary.

If Name is in the form prefix:local, then component will automatically introduce a new xmlns:prefix="NamespaceURI" as necessary.

When calling PutElement or StartElement, if a NamespaceURI is not specified, an empty namespace will be defined for the element. If a namespace should be associated with the element, a NamespaceURI value must be provided. When creating the XML, the component will determine if the namespace already exists to avoid duplicate definitions of the same namespace. For example, to create this XML:

<book xmlns='urn:loc.gov:books'
      xmlns:isbn='urn:ISBN:0-395-36341-6'>
    <title>Cheaper by the Dozen</title>
    <isbn:number>1568491379</isbn:number>
</book>

PutRaw Method (XML Component)

This method writes a raw XML fragment.

Syntax

void __fastcall PutRaw(String Text);

Remarks

This method writes a raw XML fragment to the output, without escaping and without verification. If an XML element opening tag has been written before the raw fragment, the fragment will be written as a child of the current element.

Use of this method should be carefully considered as it can easily lead to malformed XML content.

PutString Method (XML Component)

This method writes text inside an XML element.

Syntax

void __fastcall PutString(String Text);

Remarks

This method will XML escape the value provided and write the resulting escaped text between the opening and closing tags of an XML element.

RemoveAttr Method (XML Component)

This method removes an attribute.

Syntax

void __fastcall RemoveAttr(String AttrName);

Remarks

This method removes an attribute at the specified XPath

This functionality is not yet implemented.

RemoveChildren Method (XML Component)

This method removes the children of the element as the specified XPath.

Syntax

void __fastcall RemoveChildren();

Remarks

This method removes the children of the element specified by XPath.

When called, the component will remove the children of the element from the internal representation of the XML (the DOM). The element itself remains, with no children. This may be used at any time after Parse returns, or from within the EndElement event as a document is parsed to remove sections of a document that will not be needed later. By removing unnecessary elements from the DOM, memory consumption is reduced and overall performance is improved.

Example. RemoveChildren:

Given the XML

<food>
	<fruits>
		<apple>
			<color>red</color>
		</apple>
		<banana>
			<color>yellow</color>
		</banana>
	</fruits>
</food>

This code removes the children of the apple element while leaving the apple element in place.

xml.XPath = "/food/fruits/apple"; xml.RemoveChildren();

The XML stored in the DOM is now:

<food>
	<fruits>
		<apple>
		</apple>
		<banana>
			<color>yellow</color>
		</banana>
	</fruits>
</food>

RemoveElement Method (XML Component)

This method removes the element as the specified XPath.

Syntax

void __fastcall RemoveElement();

Remarks

This method removes the element specified by XPath.

When called, the component will remove the element and its children from the internal representation of the XML (the DOM). This may be used at any time after Parse returns, or from within the EndElement event as a document is parsed to remove sections of a document that will not be needed later. By removing unnecessary elements from the DOM, memory consumption is reduced and overall performance is improved.

Example. RemoveElement:

Given the XML

<food>
	<fruits>
		<apple>
			<color>red</color>
		</apple>
		<banana>
			<color>yellow</color>
		</banana>
	</fruits>
</food>

This code removes the apple element and its children.

xml.XPath = "/food/fruits/apple"; xml.RemoveElement();

The XML stored in the DOM is now:

<food>
	<fruits>
		<banana>
			<color>yellow</color>
		</banana>
	</fruits>
</food>

Reset Method (XML Component)

This method resets the parser.

Syntax

void __fastcall Reset();

Remarks

When called, the parser flushes all its buffers, firing events as necessary, and then initializes itself to its default state.

Reset must also be used as signal to the parser that the current stream of text has terminated.

Save Method (XML Component)

This method closes the component writing stream.

Syntax

void __fastcall Save();

Remarks

This method will close any open XML elements, and then close the OutputFile if necessary.

SaveDOM Method (XML Component)

This method saves the DOM to a file.

Syntax

void __fastcall SaveDOM(String FileName);

Remarks

The SaveDOM method saves the current DOM structure to the file specified in FileName. This enables the component to later load the DOM without incurring any parsing overhead.

Please refer to the LoadDOM method for more information.

StartElement Method (XML Component)

This method writes the opening tag of an XML element.

Syntax

void __fastcall StartElement(String Name, String NamespaceURI);

Remarks

This method writes the opening tag of a new XML element. If an XML element is already opened, then this element is written as a child.

If Name is a local name without a prefix, the component will automatically introduce a new xmlns="NamespaceURI" attribute, if necessary.

If Name is in the form prefix:local, then component will automatically introduce a new xmlns:prefix="NamespaceURI" as necessary.

When calling PutElement or StartElement, if a NamespaceURI is not specified, an empty namespace will be defined for the element. If a namespace should be associated with the element, a NamespaceURI value must be provided. When creating the XML, the component will determine if the namespace already exists to avoid duplicate definitions of the same namespace. For example, to create this XML:

<book xmlns='urn:loc.gov:books'
      xmlns:isbn='urn:ISBN:0-395-36341-6'>
    <title>Cheaper by the Dozen</title>
    <isbn:number>1568491379</isbn:number>
</book>

TryXPath Method (XML Component)

This method navigates to the specified XPath if it exists.

Syntax

bool __fastcall TryXPath(String xpath);

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 (XML Component)

This event is fired for plaintext segments of the input stream.

Syntax

typedef struct {
  String Text;
} TipwXMLCharactersEventParams;
typedef void __fastcall (__closure *TipwXMLCharactersEvent)(System::TObject* Sender, TipwXMLCharactersEventParams *e);
__property TipwXMLCharactersEvent OnCharacters = { read=FOnCharacters, write=FOnCharacters };

Remarks

The Characters event provides the plaintext content of the XML document (i.e., the text inside the tags). 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.

Comment Event (XML Component)

This event is fired when a comment section is encountered.

Syntax

typedef struct {
  String Text;
} TipwXMLCommentEventParams;
typedef void __fastcall (__closure *TipwXMLCommentEvent)(System::TObject* Sender, TipwXMLCommentEventParams *e);
__property TipwXMLCommentEvent OnComment = { read=FOnComment, write=FOnComment };

Remarks

The Comment event is fired whenever a comment section (<!-- ..text... -->) is found in the document.

The full text of the comment is provided by the Text parameter.

EndElement Event (XML Component)

This event is fired when an end-element tag is encountered.

Syntax

typedef struct {
  String Namespace;
  String Element;
  String QName;
  bool IsEmpty;
} TipwXMLEndElementEventParams;
typedef void __fastcall (__closure *TipwXMLEndElementEvent)(System::TObject* Sender, TipwXMLEndElementEventParams *e);
__property TipwXMLEndElementEvent OnEndElement = { read=FOnEndElement, write=FOnEndElement };

Remarks

The EndElement event is fired when an end-element tag is found in the document.

The element name is provided by the Element parameter.

The IsEmpty parameter is true when the event corresponds to an empty element declaration.

EndPrefixMapping Event (XML Component)

This event is fired when leaving the scope of a namespace declaration.

Syntax

typedef struct {
  String Prefix;
} TipwXMLEndPrefixMappingEventParams;
typedef void __fastcall (__closure *TipwXMLEndPrefixMappingEvent)(System::TObject* Sender, TipwXMLEndPrefixMappingEventParams *e);
__property TipwXMLEndPrefixMappingEvent OnEndPrefixMapping = { read=FOnEndPrefixMapping, write=FOnEndPrefixMapping };

Remarks

The StartPrefixMapping event is fired when entering the scope of a namespace declaration.

Error Event (XML Component)

Fired when information is available about errors during data delivery.

Syntax

typedef struct {
  int ErrorCode;
  String Description;
} TipwXMLErrorEventParams;
typedef void __fastcall (__closure *TipwXMLErrorEvent)(System::TObject* Sender, TipwXMLErrorEventParams *e);
__property TipwXMLErrorEvent OnError = { read=FOnError, write=FOnError };

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component raises 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.

EvalEntity Event (XML Component)

This event is fired every time an entity needs to be evaluated.

Syntax

typedef struct {
  String Entity;
  String Value;
} TipwXMLEvalEntityEventParams;
typedef void __fastcall (__closure *TipwXMLEvalEntityEvent)(System::TObject* Sender, TipwXMLEvalEntityEventParams *e);
__property TipwXMLEvalEntityEvent OnEvalEntity = { read=FOnEvalEntity, write=FOnEvalEntity };

Remarks

The Value parameter contains a suggested value for the entity (normally the entity name itself). You may set Value to a value of your choice, which will be later passed into the text stream.

IgnorableWhitespace Event (XML Component)

This event is fired when a section of ignorable whitespace is encountered.

Syntax

typedef struct {
  String Text;
} TipwXMLIgnorableWhitespaceEventParams;
typedef void __fastcall (__closure *TipwXMLIgnorableWhitespaceEvent)(System::TObject* Sender, TipwXMLIgnorableWhitespaceEventParams *e);
__property TipwXMLIgnorableWhitespaceEvent OnIgnorableWhitespace = { read=FOnIgnorableWhitespace, write=FOnIgnorableWhitespace };

Remarks

The ignorable whitespace section is provided by the Text parameter.

Meta Event (XML Component)

This event fires when a meta section is encountered.

Syntax

typedef struct {
  String Text;
} TipwXMLMetaEventParams;
typedef void __fastcall (__closure *TipwXMLMetaEvent)(System::TObject* Sender, TipwXMLMetaEventParams *e);
__property TipwXMLMetaEvent OnMeta = { read=FOnMeta, write=FOnMeta };

Remarks

The Meta event is fired whenever a meta information section (<! ..text... >) is found in the document.

The full text of the meta section is provided by the Text parameter.

PI Event (XML Component)

This event is fired when a processing instruction section is encountered.

Syntax

typedef struct {
  String Text;
} TipwXMLPIEventParams;
typedef void __fastcall (__closure *TipwXMLPIEvent)(System::TObject* Sender, TipwXMLPIEventParams *e);
__property TipwXMLPIEvent OnPI = { read=FOnPI, write=FOnPI };

Remarks

The PI event is fired whenever a processing instruction section (<? ..text... ?>) is found in the document.

The full text of the processing instruction is provided by the Text parameter.

SpecialSection Event (XML Component)

This event is fired when a special section is encountered.

Syntax

typedef struct {
  String SectionId;
  String Text;
} TipwXMLSpecialSectionEventParams;
typedef void __fastcall (__closure *TipwXMLSpecialSectionEvent)(System::TObject* Sender, TipwXMLSpecialSectionEventParams *e);
__property TipwXMLSpecialSectionEvent OnSpecialSection = { read=FOnSpecialSection, write=FOnSpecialSection };

Remarks

The SpecialSection event is fired whenever a special section (such as <![ CDATA [ ..text... ]]>) is found in the document.

The full text of the special section is provided by the Text parameter, and the SectionId parameter provides the section identifier (e.g., CDATA).

StartElement Event (XML Component)

This event is fired when a begin-element tag is encountered in the document.

Syntax

typedef struct {
  String Namespace;
  String Element;
  String QName;
  bool IsEmpty;
} TipwXMLStartElementEventParams;
typedef void __fastcall (__closure *TipwXMLStartElementEvent)(System::TObject* Sender, TipwXMLStartElementEventParams *e);
__property TipwXMLStartElementEvent OnStartElement = { read=FOnStartElement, write=FOnStartElement };

Remarks

The StartElement event is fired when a begin-element tag is found in the document.

The element name is provided through the Element parameter. The attribute names and values (if any) are provided through the AttrName, AttrNamespace, AttrPrefix, and AttrValue properties.

The IsEmpty parameter is True when the event corresponds to an empty element declaration.

StartPrefixMapping Event (XML Component)

This event is fired when entering the scope of a namespace declaration.

Syntax

typedef struct {
  String Prefix;
  String URI;
} TipwXMLStartPrefixMappingEventParams;
typedef void __fastcall (__closure *TipwXMLStartPrefixMappingEvent)(System::TObject* Sender, TipwXMLStartPrefixMappingEventParams *e);
__property TipwXMLStartPrefixMappingEvent OnStartPrefixMapping = { read=FOnStartPrefixMapping, write=FOnStartPrefixMapping };

Remarks

The EndPrefixMapping event is fired when leaving the scope of a namespace declaration.

XML Event (XML Component)

This event is fired as XML is written.

Syntax

typedef struct {
  String Text;
} TipwXMLXMLEventParams;
typedef void __fastcall (__closure *TipwXMLXMLEvent)(System::TObject* Sender, TipwXMLXMLEventParams *e);
__property TipwXMLXMLEvent OnXML = { read=FOnXML, write=FOnXML };

Remarks

This event is fired when XML is output. The Text parameter holds the data being written.

This functionality is not yet implemented.

Config Settings (XML Component)

XML Config Settings

<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
...

Base Config Settings

Trappable Errors (XML Component)

XML Errors