SDA Component

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The SDA component can be used to create a self-decrypting archive which will run natively on Windows platforms.

Syntax

TipgSDA

Remarks

The component uses the Deflate algorithm specified in RFC 1951 for compression, and then creates a self-decrypting executable archive. This exe will bring up a dialog that will allow the user to select the target directory in which to decompress the files. There is also an optional splash screen that may be displayed before decompression. The text for this splash screen may be set with the BannerText property. You can also set the text that appears on the title bar of each dialog box using the CaptionText property.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

Note: When creating a self-decrypting archive which exceeds 4 GB or more of uncompressed data or which contains more than 64K files, the component will create a 64-bit archive.

The self-decrypting archive that is created by the SDA component is a Windows application. However, there are command line options available if you wish to batch multiple files. The options are:

For example, the following suppresses all questions and message boxes, and decompress to the current directory, use the following options: SDAExtractor /targetpath="." /overwrite=1 /displaymessage=0 /openfile=0 /password=pass

Note that if you run the self-decrypting archive with any command line options, the pop up message box containing the BannerText will be suppressed.

Property List

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

Method List

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

Event List

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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

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

ArchiveFile Property (SDA Component)

The name of the self-decrypting archive to create.

Syntax

property ArchiveFile: String read get_ArchiveFile write set_ArchiveFile;

Default Value

''

Remarks

This property specifies the name of the archive to be written when CreateSDA is called. Any pre-existing archive file will be overwritten.

The filename may be specified with or without a path. Paths may be relative or absolute, and should be specified in the format native to the host operating system. The filename should be specified with the appropriate ".exe" extension. An extension will not automatically be appended by the component.

If the file cannot be written a trappable error will be generated.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

Note: When creating a self-decrypting archive which exceeds 4 GB or more of uncompressed data or which contains more than 64K files, the component will create a 64-bit archive.

BannerText Property (SDA Component)

Optional banner text to show before the self-extraction starts.

Syntax

property BannerText: String read get_BannerText write set_BannerText;

Default Value

''

Remarks

If this property is set, a dialog box will pop up displaying the contents of this property as soon as the SDA executable is run. If this property is set to an empty string (default) no banner dialog will be displayed.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

CaptionText Property (SDA Component)

Optional caption (title) text for the self-extractor dialogs.

Syntax

property CaptionText: String read get_CaptionText write set_CaptionText;

Default Value

''

Remarks

This property contains the text which will appear on the title bar of the dialog boxes that appear when running the SDA executable file. If this property is not set, "IPWorks PG Self Extractor - www.nsoftware.com" will appear in the title bar.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

CompressionLevel Property (SDA Component)

The compression level to use.

Syntax

property CompressionLevel: Integer read get_CompressionLevel write set_CompressionLevel;

Default Value

4

Remarks

This property specifies the level of compression to be used, between 0 and 6. Higher values will cause the component to compress better; lower values will cause the component to compress faster. A value of 0 will store the file without compression.

ExtractToPath Property (SDA Component)

Optional target directory for the self-extractor.

Syntax

property ExtractToPath: String read get_ExtractToPath write set_ExtractToPath;

Default Value

''

Remarks

If set to empty string (default), the self-extractor will attempt to extract files into a subdirectory of the directory it is being executed from.

The name of the subdirectory is derived from the name of the self-decrypting archive by removing its extension.

FileToExecute Property (SDA Component)

Optional file to execute (open) after the archive is extracted.

Syntax

property FileToExecute: String read get_FileToExecute write set_FileToExecute;

Default Value

'.'

Remarks

This property specifies an executable file which will be run after the archive has completed decompressing. This must be a relative path to a file located within ExtractToPath. If this property is set to ".", the folder to which the archive has been decompressed will open in Windows Explorer. If this property is set to "" (empty string), the extractor will close and take no action.

Password Property (SDA Component)

An optional password for the self-decrypting archive.

Syntax

property Password: String read get_Password write set_Password;

Default Value

''

Remarks

This property specifies a case-sensitive password used to encrypt or decrypt the archive. If set to an empty string (default), no encryption is used.

The maximum supported length of the password is 128 characters.

Example (compressing an SDA archive):

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo" component.Password = "nsoftware" component.CreateSDA()

RecurseSubdirectories Property (SDA Component)

Whether or not to recurse into subdirectories during archive creation.

Syntax

property RecurseSubdirectories: Boolean read get_RecurseSubdirectories write set_RecurseSubdirectories;

Default Value

true

Remarks

If this property is set to true, when calling CreateSDA the component will recurse into all the subdirectories under SourceDirectory and include them in the self extracting archive. If this property is false, only the files in SourceDirectory will be included in the archive.

SourceDirectory Property (SDA Component)

Directory to be compressed into a self-decrypting archive.

Syntax

property SourceDirectory: String read get_SourceDirectory write set_SourceDirectory;

Default Value

''

Remarks

This property specifies the name of the directory containing the files to be compressed. This may be a local or absolute path. If the RecurseSubdirectories property is true, all the subdirectories under SourceDirectory will be recursed into, and those files will also be compressed.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

SourceFile Property (SDA Component)

File to be compressed into a self-decrypting archive.

Syntax

property SourceFile: String read get_SourceFile write set_SourceFile;

Default Value

''

Remarks

This property specifies the name of a single file to be compressed. When both SourceFile and SourceDirectory are set, only SourceDirectory is used.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

Config Method (SDA Component)

Sets or retrieves a configuration setting.

Syntax

function Config(ConfigurationString: String): String;

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.

CreateSDA Method (SDA Component)

Compresses the files and creates a self-decrypting archive.

Syntax

procedure CreateSDA();

Remarks

Invoking CreateSDA creates the archive specified by ArchiveFile. When the method is called, all files specified by SourceDirectory will be compressed and written to ArchiveFile. If RecurseSubdirectories is true, all the subdirectories under SourceDirectory and the files they contain will also be compressed and written to ArchiveFile.

If ArchiveFile exists when you call CreateSDA it will be overwritten.

As the files in SourceDirectory are being compressed, the Progress event will fire periodically to indicate how many bytes have been processed and the percentage of compression that has been completed.

To include your own custom text on the title bar of all of the self-extractor dialog boxes, set the CaptionText before calling CreateSDA. Setting the optional BannerText property will cause a small dialog to pop up when the self-extractor is run. You can put in a description of the contents, instructions, or any text you like.

Example (Creating a Self-Decrypting Archive)

component.ArchiveFile = "c:\test.exe" component.RecurseSubdirectories = true component.SourceDirectory = "c:\foo\" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA() component.ArchiveFile = "c:\test.exe" component.SourceFile = "c:\foo\bar.dat" component.CaptionText = "Testing SDA" component.BannerText = "Press continue to decompress the archive." component.CreateSDA()

Note: When creating a self-decrypting archive which exceeds 4 GB or more of uncompressed data or which contains more than 64K files, the component will create a 64-bit archive.

The self-decrypting archive that is created by the SDA component is a Windows application. However, there are command line options available if you wish to batch multiple files. The options are:

For example, the following suppresses all questions and message boxes, and decompress to the current directory, use the following options: SDAExtractor /targetpath="." /overwrite=1 /displaymessage=0 /openfile=0 /password=pass

Note that if you run the self-decrypting archive with any command line options, the pop up message box containing the BannerText will be suppressed.

Reset Method (SDA Component)

Resets the component.

Syntax

procedure Reset();

Remarks

Reset resets the state of the component. All properties will be set to their default values, and any files open will be closed.

Error Event (SDA Component)

Information about non-fatal errors.

Syntax

type TErrorEvent = procedure (
  Sender: TObject;
  const Description: String;
  ErrorCode: Integer;
  Index: Integer;
  const Filename: String;
  var Ignore: Boolean
) of Object;

property OnError: TErrorEvent read FOnError write FOnError;

Remarks

The Error event is fired when non-fatal errors occur during compression or decompression. Note that if this event is fired during decompression this may indicate that the archive is corrupt.

By default these errors will cause the component to fail with an exception. The exception may be overridden by setting Ignore to true. This will cause the error to be ignored, the file will be skipped if necessary, and the component will continue operation.

ErrorCode will correspond to one of the following errors:

Description contains a textual description of the error. Index and Filename contain the array index (where appropriate) and filename of the file being processed at the time of the error.

Progress Event (SDA Component)

Fired as progress is made.

Syntax

type TProgressEvent = procedure (
  Sender: TObject;
  const Filename: String;
  BytesProcessed: Int64;
  PercentProcessed: Integer
) of Object;

property OnProgress: TProgressEvent read FOnProgress write FOnProgress;

Remarks

The Progress event is automatically fired as compression is performed.

Filename contains the name of the file being written.

BytesProcessed contains the total number of uncompressed bytes processed.

PercentProcessed contains the percent of uncompressed bytes processed, corresponding roughly to the running time of the operation.

Status Event (SDA Component)

Shows the progress of the operation.

Syntax

type TStatusEvent = procedure (
  Sender: TObject;
  const Message: String
) of Object;

property OnStatus: TStatusEvent read FOnStatus write FOnStatus;

Remarks

The event is fired for informational and logging purposes only. It may be used to track the progress of an operation.

The level of detail is controlled by the LogLevel setting.

Config Settings (SDA 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.

SDA Config Settings

Base Config Settings

Trappable Errors (SDA Component)

Errors

The following errors may be generated by the component. Note that frequently the error message will contain more specific information than what is listed here.

Note that some non-fatal errors may be trapped and explicitly ignored in the Error event. This will allow the component to continue operation even in case of error.

SDA Errors