Tar Component

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The Tar component implements a tar archive utility, compatible with the UNIX tar and untar utilities. The component supports the old v7 tar format. The component also implements gzip compression and can be used to create or decompress .tar.gz archives.

Syntax

TipzTar

Remarks

The interface is identical to that of the Zip component, and is the same whether gzip compression is used or not. In particular, the Compress method is used to create tar archives, even if actual compression is not used.

To create a new archive, first set the ArchiveFile property to the name of the archive to be created. Then, specify the files to be compressed either by invoking IncludeFiles, or by adding a new object to the Files collection and setting the values of the FileDecompressedName and FileCompressedName. fields. Finally, call the Compress method to create the archive.

To decompress an existing archive, set ArchiveFile to the name of the archive to be decompressed. The ExtractToPath property may be set, and then calling the ExtractAll method will decompress all files in the archive to this path.

For finer control, the Scan method should be used to read the file information stored in the archive. This will fill out the information in the Files collection. The values of FileDecompressedName may then be changed if desired. Finally, ExtractAll may be used to decompress the entire archive, or Extract may be used for finer control.

Data may be streamed out by setting WriteToProgressEvent to true. Then, the Progress event may be trapped to retrieve the data.

tar.gz files may be created or extracted by setting the UseGzipCompression property to true. When Compress is invoked, this will cause all output to be streamed through a gzip compressor as it is written. When extracting or scanning the tar archive will automatically be decompressed and written temporarily to disk. Note that this might cause Scan, Extract, and ExtractAll to operate slowly without firing events.

.gz files may also be compressed or decompressed using the Gzip component.

Example (Creating a Tar File)

ZipControl.ArchiveFile = "c:\test.tar.gz" ZipControl.RecurseSubdirectories = true ZipControl.UseGzipCompression = true ZipControl.IncludeFiles("c:\foo\*") ZipControl.Compress() Example (Extracting from a Tar File)

ZipControl.ArchiveFile = "c:\temp.tar" ZipControl.UseGzipCompression = false ZipControl.ExtractToPath = "c:\extracted\" ZipControl.ExtractAll()

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 (Tar Component)

The name of the zip, gzip, tar, or jar archive.

Syntax

__property String ArchiveFile = { read=FArchiveFile, write=FSetArchiveFile };

Default Value

""

Remarks

This property specifies the name of the archive to be read or written. This property is required when extracting files.

When Scan, Extract, or ExtractAll is invoked, the file specified by ArchiveFile will be opened for read. If the file does not exist, a trappable error will be generated.

When Compress is called, the file named by ArchiveFile will be written; if a file of this name already exists the Overwrite event will be fired. If ArchiveFile is set to the empty string (""), the archive will not be written to disk, and will be provided only through the Progress event.

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 extension (such as "zip"); an extension will not automatically be appended by the component.

If the file cannot be read, or written, as appropriate, a trappable error will be generated.

Example (Creating an Archive)

ZipControl.ArchiveFile = "c:\test.zip" ZipControl.RecurseSubdirectories = true ZipControl.IncludeFiles("c:\foo\*") ZipControl.Compress()

Note: an archive already open for read may be closed by setting ArchiveFile to the empty string ("").

Data Type

String

ExcludedFiles Property (Tar Component)

A list of files to exclude.

Syntax

__property String ExcludedFiles = { read=FExcludedFiles, write=FSetExcludedFiles };

Default Value

""

Remarks

This property specifies files that should be excluded when Compress or Extract is invoked. When Compress is invoked, each value of FileDecompressedName in Files will be compared to ExcludedFiles, and each file will be excluded if the name matches. When Extract is called, each value of FileCompressedName in Files matching the parameter to Extract will be compared to ExcludedFiles, and will be excluded if appropriate. Calling the ExtractAll method will ignore this property and extract all files in the archive.

This property may be set to one or more filenames or directory names. Files may be specified with or without a path, and with or without wildcards. If a path is specified, files in the indicated directory will be excluded; subdirectories will be recursed into if RecurseSubdirectories is true. If no path is specified but wildcards are, matching files in all directories will be excluded. If a single filename without a path is specified, it must correspond exactly to the appropriate value of FileCompressedName or FileDecompressedName.

Directories should end with a slash ("/" or "\", as appropriate.) If a directory is specified, all files and subdirectories in the specified directory will be excluded.

A pipe character ("|") should be used to separate multiple file or directory names.

The following examples illustrate the use of the property:

Example

ZipControl.ArchiveFile = "c:\test.zip" ZipControl.IncludeFiles("c:\test\*") ZipControl.ExcludedFiles = "*.tmp" ZipControl.Compress() Example

ZipControl.ArchiveFile = "c:\test.tar" ZipControl.Scan() ZipControl.ExcludedFiles = "*.bak | backup/" ZipControl.ExtractToPath = "c:\temp" ZipControl.Extract("*") As per the examples, the property should be specified differently for compression and decompression. When invoking Compress, the format of ExcludedFiles should correspond to that of the local file system. When invoking Extract the format should correspond to standard (UNIX) format, and should not contain drive letters or backslashes.

You may exclude files based on their attributes as well: See the ExcludedAttributes configuration setting for more information.

If the property is set to the empty string, no files will be excluded. This property is never reset automatically, so be sure to reset it manually if using a single instance of the component for both compression and extraction. Failure to do so may result in I/O errors or unexpected results.

Data Type

String

ExtractToPath Property (Tar Component)

A base path to decompress to.

Syntax

__property String ExtractToPath = { read=FExtractToPath, write=FSetExtractToPath };

Default Value

""

Remarks

Setting the ExtractToPath property affects the operation of the Extract and ExtractAll methods. Setting this property to a nonempty string will cause all decompressed files to be written to the specified path. If pathnames are given in the values of FileDecompressedName they will be regarded as relative to ExtractToPath.

If the specified directory does not exist, it will be created when extraction is done.

ExtractToPath should always be specified in the format native to the host operating system, and with a trailing slash or backslash. If the path is specified otherwise, it will be immediately converted and stored in the converted format. For example, "/temp" would be immediately converted to "\temp\" on a Windows system.

Example (Extracting from an Archive)

ZipControl.ArchiveFile = "c:\temp.zip" ZipControl.ExtractToPath = "c:\extracted\" ZipControl.ExtractAll()

Example - Adding Files Dim i as Integer ZipControl.ArchiveFile = "c:\test.zip" ZipControl.Scan() For i = 0 to ZipControl.Files.Count - 1 ZipControl.Files(i).DecompressedName(i) = "c:\temp\" + ZipControl.Files(i).DecompressedName Next i ZipControl.ExtractToPath = "" ZipControl.ExtractAll() ZipControl.IncludeFiles("c:\extra\*") ZipControl.Compress()

Data Type

String

FileCount Property (Tar Component)

The number of records in the File arrays.

Syntax

__property int FileCount = { read=FFileCount, write=FSetFileCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• FileCompressedDate
• FileCompressedName
• FileCompressedSize
• FileDecompressedName
• FileDecompressedSize
• FileHardLinkName
• FileInputData
• FilePermissions
• FileSymLinkName

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

This property is not available at design time.

Data Type

Integer

FileCompressedDate Property (Tar Component)

The date and time of the entry, as stored within the archive.

Syntax

__property __int64 FileCompressedDate[int FileIndex] = { read=FFileCompressedDate, write=FSetFileCompressedDate };

Default Value

0

Remarks

The date and time of the entry, as stored within the archive.

FileCompressedDate contains the last modified date of the file, as stored within the archive (it does not generally correspond to when the file was compressed).

FileCompressedDate is returned in a platform-specific format. The Java,C++, and most other Editions will return the number of milliseconds since January 1, 1970, 00:00:00. This value may be passed directly to the java.util.Date constructor to create a java.util.Date object representing this date.

The .NET Edition will return the number of ticks, or 100-nanosecond intervals, since January 1, 0001, 00:00:00. This value may be passed directly to the System.DateTime constructor to create a System.DateTime object representing this date.

Reading the value of this property will return a meaningful value only after the archive has been successfully scanned or decompressed, and only if the values of ArchiveFile, Files collection, and FileCompressedName have not been changed since. If a meaningful value is not available this property will return a value of 0.

NOTE: This may be set accordingly when the FileInputStream property is set to a valid stream to input the data for the current file. If not set, the default, 0, is used. Otherwise the value is read from disk.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

Long64

FileCompressedName Property (Tar Component)

The file name of the current file, as stored inside of the archive.

Syntax

__property String FileCompressedName[int FileIndex] = { read=FFileCompressedName, write=FSetFileCompressedName };

Default Value

""

Remarks

The file name of the current file, as stored inside of the archive. This may be the same as in FileDecompressedName, but is not required to be.

All paths are stored in the archive in standard (UNIX) format. Pathnames specified in the host operating system's format will be immediately converted.

This field should generally be set with a relative path or with no path at all. The exact interpretation of the path is left to the decompression software; generally, pathnames will be interpreted as relative to a base directory, and these subdirectories will be created as needed. Absolute pathnames (paths beginning with a / character) will not be interpreted correctly by the component, and may or may not be interpreted correctly by other decompression software.

Paths should be specified in standard (UNIX) format. They may also be specified in the format native to the host operating system, in which case they will be immediately converted.

Example

ZipControl.ArchiveFile = "c:\test.zip" ZipControl.Files.Add(new ZIPFile()) ZipControl.Files[0].DecompressedName = "c:\test\ipworkszip\temp\test.txt" ZipControl.Files[0].CompressedName = "readme.txt" ZipControl.Compress()

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

String

FileCompressedSize Property (Tar Component)

The size of the compressed data, as compressed within the archive.

Syntax

__property __int64 FileCompressedSize[int FileIndex] = { read=FFileCompressedSize };

Default Value

-1

Remarks

The size of the compressed data, as compressed within the archive. Headers, footers, etc., are not included in the size.

Reading the value of this property will return a meaningful value only after the archive has been compressed, scanned, or decompressed, and only if the values of ArchiveFile, or Files have not been changed since. If a meaningful value is not available this property will return a value of -1.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

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

Data Type

Long64

FileDecompressedName Property (Tar Component)

The name of the file in the archive, as stored on the file system, outside the archive.

Syntax

__property String FileDecompressedName[int FileIndex] = { read=FFileDecompressedName, write=FSetFileDecompressedName };

Default Value

""

Remarks

The name of the file in the archive, as stored on the file system, outside the archive.

When compressing files, This property should be specified with a path, if necessary, to allow the file to be found by the component. If the file cannot be found during compression, a trappable error will be generated, and the archive will not be correctly written.

When decompressing files, the property indicates where the file should be written. After the archive is scanned, the values of FileCompressedName and DecompressedName will be set to the exact filenames found in the archive. The value of DecompressedName may then be changed if desired.

If DecompressedName is set to an empty string before extraction, the file will not be written to disk at all. It will still be written to the Progress event if WriteToProgressEvent is set to true.

If DecompressedName is set to an empty string before compression, the file will be skipped, and not written to the archive.

A base path for decompression may be specified by setting the ExtractToPath property. If ExtractToPath is set to a non-empty string, the files will be decompressed to the directory specified in ExtractToPath. If the value of FileDecompressedName contains a pathname it will be regarded as relative to ExtractToPath.

Paths on the local file system should be specified in the format native to the host operating system. They may also be specified in standard (UNIX) format, in which case they will be immediately converted.

Example

ZipControl.ArchiveFile = "c:\test.tar" ZipControl.Scan() ZipControl.ExtractToPath = "c:\temp\" ZipControl.Files[1].DecompressedName = "test\temp.out" ZipControl.Extract(ZipControl.Files[1].CompressedName) Incorrect Example ZipControl.ExtractToPath = "c:\temp\" ZipControl.Files[1].DecompressedName = "c:\temp\test\temp.out" 'The file would be extracted to c:\temp\c:\temp\test\temp.out

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

String

FileDecompressedSize Property (Tar Component)

The size of the file, as decompressed outside the archive.

Syntax

__property __int64 FileDecompressedSize[int FileIndex] = { read=FFileDecompressedSize };

Default Value

-1

Remarks

The size of the file, as decompressed outside the archive. If an archive is open for read (i.e. has been scanned or decompressed), this information will be read from the archive headers. If an archive is not open for read, the component will retrieve the information for the corresponding value of FileDecompressedName from the local file system.

A value of -1 will be returned in case of an I/O error.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

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

Data Type

Long64

FileHardLinkName Property (Tar Component)

The hard link name, for a file that represents a hard link.

Syntax

__property String FileHardLinkName[int FileIndex] = { read=FFileHardLinkName, write=FSetFileHardLinkName };

Default Value

""

Remarks

The hard link name, for a file that represents a hard link. If you specify FileHardLinkName the file will be added to the tar file as a hard link. You should specify the name of the link in FileCompressedName and the name of the linked file in FileHardLinkName.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

String

FileInputData Property (Tar Component)

When This property is set, the component will read in the data from This property instead of reading from the file contained in the DecompressedName property.

Syntax

__property String FileInputData[int FileIndex] = { read=FFileInputData, write=FSetFileInputData };
__property DynamicArray<Byte> FileInputDataB[int FileIndex] = { read=FFileInputDataB, write=FSetFileInputDataB };

Default Value

""

Remarks

When This property is set, the component will read in the data from This property instead of reading from the file contained in the FileDecompressedName property.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

Byte Array

FilePermissions Property (Tar Component)

This property contains the UNIX permissions of the file, as stored in the tar archive.

Syntax

__property String FilePermissions[int FileIndex] = { read=FFilePermissions, write=FSetFilePermissions };

Default Value

"644"

Remarks

This property contains the UNIX permissions of the file, as stored in the tar archive. It will be written to the tar archive during compression. As native code is not used, permissions are read from and written to the tar archive only, and not to the file system.

The value should be specified as a string of three characters, representing the owner's permissions, the group's permissions, and others' permissions. Each character should be a bitmask of 4 (read access), 2 (write access), or 1 (executable access), as in chmod.

In Java, if the SetFilePermissions configuration setting is set to true, the component will shell out an instance of chmod for each file, and will attempt to set the file permissions to those specified in FilePermissions. Obviously, this functionality is operating system dependent and will fail in Windows in particular; it may also fail in other operating systems for a variety of reasons.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

String

FileSymLinkName Property (Tar Component)

The symbolic link name, for a file that represents a symbolic link.

Syntax

__property String FileSymLinkName[int FileIndex] = { read=FFileSymLinkName, write=FSetFileSymLinkName };

Default Value

""

Remarks

The symbolic link name, for a file that represents a symbolic link. If you specify FileSymLinkName the file will be added to the tar file as a symbolic link. You should specify the name of the link in FileCompressedName and the name of the linked file in FileSymLinkName.

The FileIndex parameter specifies the index of the item in the array. The size of the array is controlled by the FileCount property.

This property is not available at design time.

Data Type

String

OverwriteFiles Property (Tar Component)

Whether or not to overwrite files.

Syntax

__property bool OverwriteFiles = { read=FOverwriteFiles, write=FSetOverwriteFiles };

Default Value

true

Remarks

If this property is set to true, existing files will be overwritten when decompressing. When Extract or ExtractAll is called, each file specified in Files will be checked for existence. If a file exists, the Overwrite event will be fired, and the files will be overwritten if OverwriteFiles is set to true.

More precise control of which files should be overwritten may be gained by listening to the Overwrite event and altering its parameters when the event is fired.

This property only affects the operation of Extract and ExtractAll. When compressing files, ArchiveFile will always be overwritten unless the user specifies otherwise in the Overwrite event.

Data Type

Boolean

RecurseSubdirectories Property (Tar Component)

Whether or not to recurse into subdirectories.

Syntax

__property bool RecurseSubdirectories = { read=FRecurseSubdirectories, write=FSetRecurseSubdirectories };

Default Value

true

Remarks

This property affects the behavior of IncludeFiles and Extract and the meaning of ExcludedFiles. If this property is set to true, IncludeFiles will recurse into all subdirectories whenever it performs a search on the file system.

Be sure RecurseSubdirectories is set to the appropriate value before invoking IncludeFiles, Extract, or Compress; changing the value of this property after method calls will not retroactively alter their effects.

Example (Creating an Archive)

ZipControl.ArchiveFile = "c:\test.zip" ZipControl.RecurseSubdirectories = true ZipControl.IncludeFiles("c:\foo\*") ZipControl.Compress()

Data Type

Boolean

TarData Property (Tar Component)

(Decompression only) The tar file contents as a byte array.

Syntax

__property String TarData = { write=FSetTarData };
__property DynamicArray<Byte> TarDataB = { write=FSetTarDataB };

Default Value

""

Remarks

Normally you should set ArchiveFile before invoking Scan or Extract. If you prefer to read the tar file from memory you may set TarData instead. TarData should be set to the entire contents of the tar file; this will allow you to read from the archive without writing any temporary files to disk.

If you would like to extract data from the archive without ever writing to disk you should also set WriteToProgressEvent to true, and after invoking Scan, you should set the value of FileDecompressedName for each file in the Files collection to an empty string. Then, when you invoke Extract (or ExtractAll) the data will be provided in the Progress event.

This property is write-only. Note that modifying a tar file stored in TarData is not supported, so Append, Delete, etc., will throw exceptions.

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

Data Type

Byte Array

UseGzipCompression Property (Tar Component)

Whether or not to use gzip compression.

Syntax

__property bool UseGzipCompression = { read=FUseGzipCompression, write=FSetUseGzipCompression };

Default Value

false

Remarks

If this property is set to true, the component will operate on tar archives that have been compressed with gzip. The interface of the component remains the same. During compression, the data will be streamed through a gzip compressor as it is written to the file. During decompression, the component will unzip the data to a temporary tar archive, and then automatically scan or decompress the tar archive.

The creation of the temporary tar file will occur when the Scan method is invoked (note that this method is invoked automatically by Extract and ExtractAll if it is not invoked explicitly by the user). The entire file must be decompressed, so Scan might operate slowly, and the Progress event will be fired as the tar file is extracted. If Scan is invoked automatically by Extract or ExtractAll, the PercentProcessed parameter of the event will increase from 0 to 100 as the archive is decompressed, and again as files are extracted from the temporary file.

The temporary file will automatically be deleted by the component after it is no longer needed. To extract the tar file itself (rather than its contents), the Gzip component should be used.

Due to the nature of the gzip format, Append and Delete are not supported for .tar.gz files.

If this property is set to false, the component will create and read ordinary, uncompressed tar archives.

NOTE: This is not supported when using an input stream for extraction.

Data Type

Boolean

Abort Method (Tar Component)

Aborts the current operation.

Syntax

void __fastcall Abort();

Remarks

Abort may be used to immediately interrupt compression or decompression. Any files partially written by the component will be deleted.

In case Append or Delete is aborted the archive will be left in its original state.

Append Method (Tar Component)

Adds a file to an existing archive.

Syntax

void __fastcall Append(String DecompressedName, String CompressedName);

Remarks

Append may be used to add a file to an existing archive. Unlike IncludeFiles, Append compresses and adds the file to the archive as soon as it is invoked.

DecompressedName should be set to the name of the single file to be added. It should be specified with a path if necessary, to allow the component to find it. The value of CompressedName is the name that will be stored in the archive.

When Append is invoked, the Scan method will first be invoked, if it has not been invoked already. Note that if IncludeFiles has been invoked, or if the values of FileCompressedName and FileDecompressedName have been set for that file in the Files collection, this information will be reset by the call to Scan.

After the file is added, the array properties will be updated appropriately.

This method may only be used to add a file to an existing archive. To add files to a new archive, the IncludeFiles and Compress methods should be used.

Due to the nature of the gzip format, Append and Delete are not supported for .tar.gz files.

Compress Method (Tar Component)

Creates the compressed archive.

Syntax

void __fastcall Compress();

Remarks

Invoking Compress creates the archive specified by ArchiveFile. When the method is called, all files specified by the FileDecompressedName field of the Files collection will be compressed and written to ArchiveFile.

The compressed data may be streamed out by setting WriteToProgressEvent to true. If streaming is enabled the compressed data will also be provided via the Progress event. If ArchiveFile is set to an empty string the archive will be written only to this event.

The files to compress are specified in the Files collection. The file names are specified by FileCompressedName and FileDecompressedName. These should be specified before invoking Compress, either manually or by invoking IncludeFiles.

The BeginFile and EndFile events will be fired as files are processed, and the Progress event will be fired as data is compressed.

Existing files will be overwritten by the component if OverwriteFiles is set to true. Finer control over which files are overwritten may be gained by trapping the Overwrite event.

Example (Creating an Archive)

ZipControl.ArchiveFile = "c:\test.zip" ZipControl.RecurseSubdirectories = true ZipControl.IncludeFiles("c:\foo\*") ZipControl.Compress()

Config Method (Tar 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.

Delete Method (Tar Component)

Deletes one or more files from an existing archive.

Syntax

void __fastcall Delete(String FileNames);

Remarks

Delete deletes one or more files from an existing archive, without reprocessing the compressed data. The archive will be opened immediately, and the file(s) will immediately be removed permanently from the archive.

The list of filenames should be specified exactly as when calling Extract:

Filenames may be set to one or more filenames or directory names. Files may be specified with or without a path, and with or without wildcards. If a path is specified, files in the indicated directory will be affected; subdirectories will be recursed into if RecurseSubdirectories is true. If no path is specified but wildcards are, matching files in all directories will be affected. If a single filename without a path is specified, it must correspond exactly to the appropriate value of FileCompressedName.

Directories should end with a slash ("/"). If a directory is specified, all files and subdirectories in the specified directory will be affected.

A pipe character ("|") should be used to separate multiple file or directory names. Alternatively, the method may be invoked repeatedly.

The ExcludedFiles property may be used to further limit the files to be deleted. When Delete is used to delete a directory or match wildcards, each file to be deleted is first compared against ExcludedFiles, and any files marked as excluded will not be deleted. When Delete is used to delete a single file, the value of ExcludedFiles will be ignored.

When the method is invoked, the Scan method will first be invoked, if it has not been invoked already. Note that if IncludeFiles has been invoked, or if the values of FileCompressedName and FileDecompressedName for each file in the Files collection have been set, this information will be reset by the call to Scan.

When deleting multiple files, the component will operate most efficiently if all filenames are passed to Delete in a single invocation of the method. Invoking Delete repeatedly on large archives is not recommended.

Invoking Delete will only remove files from ArchiveFile; it will not delete the files from the disk.

Example

ZipControl.ArchiveFile = "c:\\test.zip" ZipControl.Delete("default_readme.txt"); ZipControl.Append("\\mydir\\my_readme.txt", "my_readme.txt")

Extract Method (Tar Component)

Extracts a single file, directory, or group of files, from the archive.

Syntax

void __fastcall Extract(String FileNames);

Remarks

Extract extracts one or more files from the archive. The file(s) will be extracted to the directory specified by ExtractToPath, and given the names found in the archive or specified by the FileDecompressedName of the file in the Files collection.

Filenames may be set to one or more filenames or directory names. Files may be specified with or without a path, and with or without wildcards. If a path is specified, files in the indicated directory will be affected; subdirectories will be recursed into if RecurseSubdirectories is true. If no path is specified but wildcards are, matching files in all directories will be affected. If a single filename without a path is specified, it must correspond exactly to the appropriate value of FileCompressedName.

Directories should end with a slash ("/"). If a directory is specified, all files and subdirectories in the specified directory will be affected.

A pipe character ("|") should be used to separate multiple file or directory names. Alternatively, the method may be invoked repeatedly.

The ExcludedFiles property may be used to further limit the files to be extracted. When Extract is used to extract a directory or match wildcards, each file to be extracted is first compared against ExcludedFiles, and any files marked as excluded will not be extracted. When Extract is used to extract a single file, the value of ExcludedFiles will be ignored.

To extract all files in the archive, the ExtractAll method may be used.

The BeginFile and EndFile events will be fired before and after each file is extracted, and the Progress event will be fired as the data is extracted. If WriteToProgressEvent is set to true, the decompressed data will be streamed out through the Progress event.

Example

ZipControl.ArchiveFile = "c:\test.tar" ZipControl.ExcludedFiles = "*.bak | backup/" ZipControl.ExtractToPath = "c:\temp" ZipControl.Extract("*") Example ZipControl.ArchiveFile = "c:\test.zip" ZipControl.ExcludedFiles = "" ZipControl.ExtractToPath = "c:\temp" ZipControl.Extract("code/") Example ZipControl.ArchiveFile = "c:\test.jar" ZipControl.ExcludedFiles = "*.txt" ZipControl.ExtractToPath = "c:\" ZipControl.Extract("* | docs/readme.txt")

ExtractAll Method (Tar Component)

Extracts all files from the compressed archive.

Syntax

void __fastcall ExtractAll();

Remarks

ExtractAll extracts all files from the archive. The file(s) will be extracted to the directory specified by ExtractToPath, and given the names found in the archive or specified by the FileDecompressedName field of the file in the Files collection.

If Scan has not been invoked when ExtractAll is called, Scan will automatically be invoked, and the Files collection will be set to the values found in the archive. To manually set the decompressed filenames, Scan should be invoked before setting the FileDecompressedName field.

Invoking this method is equivalent to setting ExcludedFiles to the empty string, and then invoking Extract with "*" as the argument. Calling this method will cause the ExcludedFiles property to be ignored; to extract all files except those specified by ExcludedFiles, call the Extract method with the wildcard "*" as the method parameter instead of calling this method.

The BeginFile and EndFile events will be fired before and after each file is extracted, and the Progress event will be fired as the data is extracted. If WriteToProgressEvent is set to true, the decompressed data will be streamed out through the Progress event.

Example (Extracting from an Archive)

ZipControl.ArchiveFile = "c:\temp.zip" ZipControl.ExtractToPath = "c:\extracted\" ZipControl.ExtractAll()

IncludeFiles Method (Tar Component)

Specifies that the indicated files should be added to the archive.

Syntax

void __fastcall IncludeFiles(String FileNames);

Remarks

IncludeFiles may be used before Compress, to specify the files to be compressed. Invoking this method populates the Files collection accordingly.

Invoking the method does not create or alter the archive.

The argument should be a pipe ("|") -delimited sequence of one or more filenames. The filenames should be specified with paths if necessary, so that the files may be found on the local file system. The filenames will be stored as is in the FileDecompressedName field, and without a pathname in the FileCompressedName field of the Files collection.

Filenames may include the wildcards '?', '*', and '[ .. ]'. '?' will match any single character, and '*' will match an arbitrary sequence of characters. '[ .. ]' may be used to match any of the characters inside, or a range, such as '[a-z]'. A '\' can be used to escape wildcard characters.

If wildcards are specified, the file system will be scanned and all files matching the specified mask will be added. Moreover, subdirectories will be recursed into if RecurseSubdirectories is set to true. When recursing into subdirectories, relative path information will be stored in FileCompressedName field of the Files collection.

The ExcludedFiles may be used to limit the files to be compressed. This property is checked when Compress is invoked, rather than when IncludeFiles is invoked, so this property may be set before or after invoking IncludeFiles.

Note that invoking IncludeFiles will not reset the component, or remove old values of FileCompressedName and FileDecompressedName. This may be done by first clearing the Files collection.

Example

ZipControl.IncludeFiles("c:\test\* | c:\readme") ZipControl.ExcludedFiles = "*.tmp" ZipControl.Compress()

Reset Method (Tar Component)

Resets the component.

Syntax

void __fastcall Reset();

Remarks

Reset resets the state of the component. The Files collection will be cleared, all properties will be set to their default values, and any files open will be closed.

Scan Method (Tar Component)

Scans the compressed archive.

Syntax

void __fastcall Scan();

Remarks

This method will scan the archive specified by ArchiveFile. The number of files and their names and sizes will be determined and written to the Files collection.

After scanning the archive, the values of FileDecompressedName may be changed if desired, and any number of files may be decompressed. The Extract method allows you to decompress files of your choice, and the ExtractAll method will decompress the entire archive.

Changing the values of the FileCompressedName field or the number of files in the Files collection will invalidate the scan. If either of these is changed and Extract or ExtractAll is then called; Scan will automatically be called again, and these values will be reset to their original values.

Calling this method will frequently generate a trappable error if the archive is corrupt. This is not guaranteed, however, as Scan only examines the headers.

Example

Dim i As Integer ZipControl.ArchiveFile = "c:\temp.zip" ZipControl.Scan For i = 0 To ZipControl.FileCount - 1 Debug.Print "File Name: " & ZipControl.FileDecompressedName(i) Debug.Print "File Size: " & ZipControl.FileDecompressedSize(i) Next i

BeginFile Event (Tar Component)

Fired before each file is processed.

Syntax

typedef struct {
  int Index;
  bool Skip;
} TipzTarBeginFileEventParams;
typedef void __fastcall (__closure *TipzTarBeginFileEvent)(System::TObject* Sender, TipzTarBeginFileEventParams *e);
__property TipzTarBeginFileEvent OnBeginFile = { read=FOnBeginFile, write=FOnBeginFile };

Remarks

BeginFile is fired before each file is processed by the compressor or decompressor, as appropriate. Index contains the array index of the file about to be processed, and the FileCompressedName, FileDecompressedName, FileCompressedSize (decompression only), and FileDecompressedSize fields of the Files collection for this index contain more detailed information about the file about to be processed.

When extracting, an alternate location may be specified by trapping the event, and modifying FileDecompressedName and/or ExtractToPath. If FileDecompressedName is set to an empty string, the file will not be written to disk. If WriteToProgressEvent is true, the file will still be decompressed, and the data may be extracted through the Progress event.

This event may also be trapped while compressing. FileCompressedName and FileDecompressedName may be changed.

You may set the Skip parameter to true in order to skip the file completely while compressing or extracting.

EndFile Event (Tar Component)

Fired after each file is processed.

Syntax

typedef struct {
  int Index;
} TipzTarEndFileEventParams;
typedef void __fastcall (__closure *TipzTarEndFileEvent)(System::TObject* Sender, TipzTarEndFileEventParams *e);
__property TipzTarEndFileEvent OnEndFile = { read=FOnEndFile, write=FOnEndFile };

Remarks

EndFile is fired after each file is processed by the compressor or decompressor, as appropriate. Index contains the array index of the file processed, and the FileCompressedName, FileDecompressedName, FileCompressedSize, and FileDecompressedSize fields in the Files collection for this index contain more detailed information about the file processed.

Error Event (Tar Component)

Information about non-fatal errors.

Syntax

typedef struct {
  String Description;
  int ErrorCode;
  int Index;
  String Filename;
  bool Ignore;
} TipzTarErrorEventParams;
typedef void __fastcall (__closure *TipzTarErrorEvent)(System::TObject* Sender, TipzTarErrorEventParams *e);
__property TipzTarErrorEvent OnError = { 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.

Overwrite Event (Tar Component)

Fired whenever a file exists and may be overwritten.

Syntax

typedef struct {
  String Filename;
  bool Overwrite;
} TipzTarOverwriteEventParams;
typedef void __fastcall (__closure *TipzTarOverwriteEvent)(System::TObject* Sender, TipzTarOverwriteEventParams *e);
__property TipzTarOverwriteEvent OnOverwrite = { read=FOnOverwrite, write=FOnOverwrite };

Remarks

Overwrite is fired when a file is about to be overwritten, and would overwrite an existing file. The event is fired during decompression.

Filename contains the full name of the file, specified with its pathname.

Overwrite specifies whether or not the file will be overwritten. For Zip, Jar, and Tar, this is equal by default to the value of the OverwriteFiles property. For Gzip, this value defaults to true.

Either of the parameters may be changed when the event is fired. Changing the value of Overwrite will override the default behavior of the component, and cause the file to be overwritten or not overwritten, depending on the value set. If Filename is changed, the value of Overwrite will be ignored, and the file will be written with the specified name. If a file of the new name also exists this file will be silently overwritten.

Progress Event (Tar Component)

Fired as progress is made.

Syntax

typedef struct {
  String Data;
  DynamicArray<Byte> DataB;
  String Filename;
  __int64 BytesProcessed;
  int PercentProcessed;
} TipzTarProgressEventParams;
typedef void __fastcall (__closure *TipzTarProgressEvent)(System::TObject* Sender, TipzTarProgressEventParams *e);
__property TipzTarProgressEvent OnProgress = { read=FOnProgress, write=FOnProgress };

Remarks

The Progress event is automatically fired as compression or decompression is performed. When WriteToProgressEvent is true, the output data is provided through the Data parameter, allowing for it to be streamed out.

Filename contains the name of the file being written. If no file is being written, Filename will contain an empty string, and the output data will be provided exclusively through this event.

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.

For Gzip extraction only, BytesProcessed and PercentProcessed will reflect the number of compressed bytes extracted, as it is generally impossible to predetermine the total uncompressed size.

If WriteToProgressEvent is false, Data will contain null.

Config Settings (Tar 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.

Tar Config Settings

Base Config Settings

Trappable Errors (Tar 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.

Tar Errors