TChilkatGzip Delphi ActiveX Reference Documentation

TChilkatGzip

GZip compression component.

Importing the Chilkat ActiveX into Delphi

Important: Whenever upgrading to a new version of Chilkat, make sure to re-imported ActiveX DLL into Delphi to regenerate the files described below.

Two things are required to use an ActiveX in Delphi:

  1. The ActiveX DLL needs to be registered via regsvr32 on the system where the Delphi application runs. See How To Register ActiveX DLLs for detailed information.
  2. The ActiveX component needs to be "imported". Use the Delphi Import Component Wizard to import the Chilkat type library. This creates the following files: Chilkat_v9_5_0_TLB.pas and Chilkat_v9_5_0_TLB.dcr. The Chilkat_v9_5_0_TLB.pas should be added to your project.

To import the Chilkat type library, do the following:

  1. In the Delphi RAD Studio, select the menu item "Component" --> "Import a Type Library".
  2. Find "Chilkat ActiveX v9.5.0" in the list and select it. This will only appear in the list if the ChilkatAx-9.5.0-win32.dll (or ChilkatAx-9.5.0-x64.dll) has been registered w/ regsvr32.
  3. Check the "Generate Component Wrappers" checkbox.
  4. Select a directory where the unit files (.pas and .dcr) will be generated.
  5. Select "Create Unit" and then "Finish".
  6. Add the .pas to your Delphi project.

To use a Chilkat ActiveX object in your Delphi code, add "Chilkat_v9_5_0_TLB" to the "uses" statement. For example:

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_v9_5_0_TLB;

Object Creation

var
obj: TChilkatGzip;
...
begin
obj := TChilkatGzip.Create(Self);
...
// When finished, free the object instance.
obj.Free();

Properties

property AbortCurrent: Integer

Introduced in version 9.5.0.58

When set to 1, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to 0 when the next method is called. When the abort occurs, this property is reset to 0. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

property Comment: WideString

Specifies an optional comment string that can be embedded within the .gz when any Compress* method is called.

property CompressionLevel: Integer

Introduced in version 9.5.0.50

The compression level to be used when compressing. The default is 6, which is the typical value used for zip utility programs when compressing data. The compression level may range from 0 (no compression) to 9 (the most compression). The benefits of trying to increase compression may not be worth the added expense in compression time. In many cases (which is data dependent), the improvement in compression is minimal while the increase in computation time is significant.

property DebugLogFilePath: WideString

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

property ExtraData: OleVariant

Optional extra-data that can be included within a .gz when a Compress* method is called.

property Filename: WideString

The filename that is embedded within the .gz during any Compress* method call. When extracting from a .gz using applications such as WinZip, this will be the filename that is created.

property HeartbeatMs: Integer

The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.

property LastBinaryResult: OleVariant readonly

Introduced in version 9.5.0.52

The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).

property LastErrorHtml: WideString readonly

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastErrorText: WideString readonly

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

Concept of LastErrorText

LastErrorText Standard Information

property LastErrorXml: WideString readonly

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastMethodSuccess: Integer

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = 1 and failure = 0.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

property LastMod: TDateTime

This property is deprecated. It will be removed in a future version.

The last-modification date/time to be embedded within the .gz when a Compress* method is called. By default, the current system date/time is used.

property LastModStr: WideString

The same as the LastMod property, but allows the date/time to be get/set in RFC822 string format.

property LastStringResult: WideString readonly

Introduced in version 9.5.0.52

The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).

Long Strings Returned by ActiveX Methods in SQL Server

property LastStringResultLen: Integer readonly

Introduced in version 9.5.0.53

The length, in characters, of the string contained in the LastStringResult property.

property UseCurrentDate: Integer

If set to 1, the file produced by an Uncompress* method will use the current date/time for the last-modification date instead of the date/time found within the Gzip format.

property VerboseLogging: Integer

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

property Version: WideString readonly

Version of the component/library, such as "9.5.0.63"

Methods

function CompressBd(binDat: TChilkatBinData): Integer;

Introduced in version 9.5.0.67

In-place gzip the contents of binDat.

Returns 1 for success, 0 for failure.

Gzip Compress In Memory and Base64 Encode

function CompressBdAsync(binDat: TChilkatBinData): TChilkatTask;

Introduced in version 9.5.0.67

Creates an asynchronous task to call the CompressBd method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressFile(inFilename: WideString; destPath: WideString): Integer;

Compresses a file to create a GZip compressed file (.gz).

Returns 1 for success, 0 for failure.

function CompressFileAsync(inFilename: WideString; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressFile2(inFilename: WideString; embeddedFilename: WideString; destPath: WideString): Integer;

Compresses a file to create a GZip compressed file (.gz). inFilename is the actual filename on disk. embeddedFilename is the filename to be embedded in the .gz such that when it is un-gzipped, this is the name of the file that will be created.

Returns 1 for success, 0 for failure.

function CompressFile2Async(inFilename: WideString; embeddedFilename: WideString; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressFile2 method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressFileToMem(inFilename: WideString): OleVariant;

Gzip compresses a file to an in-memory image of a .gz file.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function CompressFileToMemAsync(inFilename: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressFileToMem method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressMemory(inData: OleVariant): OleVariant;

Compresses in-memory data to an in-memory image of a .gz file.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function CompressMemoryAsync(inData: OleVariant): TChilkatTask;

Creates an asynchronous task to call the CompressMemory method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressMemToFile(inData: OleVariant; destPath: WideString): Integer;

Gzip compresses and creates a .gz file from in-memory data.

Returns 1 for success, 0 for failure.

function CompressMemToFileAsync(inData: OleVariant; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressMemToFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressString(inStr: WideString; destCharset: WideString): OleVariant;

Gzip compresses a string and writes the output to a byte array. The string is first converted to the charset specified by destCharset. Typical charsets are "utf-8", "iso-8859-1", "shift_JIS", etc.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

Full List of Charset Names

function CompressStringAsync(inStr: WideString; destCharset: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressString method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function CompressStringENC(inStr: WideString; charset: WideString; encoding: WideString): WideString;

The same as CompressString, except the binary output is returned in encoded string form according to the encoding. The encoding can be any of the following: "Base64", "modBase64", "Base32", "UU", "QP" (for quoted-printable), "URL" (for url-encoding), "Hex", "Q", "B", "url_oath", "url_rfc1738", "url_rfc2396", and "url_rfc3986".

Returns a zero-length WideString on failure

function CompressStringToFile(inStr: WideString; destCharset: WideString; destPath: WideString): Integer;

Gzip compresses a string and writes the output to a .gz compressed file. The string is first converted to the charset specified by destCharset. Typical charsets are "utf-8", "iso-8859-1", "shift_JIS", etc.

Returns 1 for success, 0 for failure.

Full List of Charset Names

function CompressStringToFileAsync(inStr: WideString; destCharset: WideString; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the CompressStringToFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function Decode(encodedStr: WideString; encoding: WideString): OleVariant;

Decodes an encoded string and returns the original data. The encoding mode is determined by encoding. It may be "base64", "hex", "quoted-printable", or "url".

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function DeflateStringENC(inString: WideString; charsetName: WideString; outputEncoding: WideString): WideString;

Provides the ability to use the zip/gzip's deflate algorithm directly to compress a string. Internal to this method, inString is first converted to the charset specified by charsetName. The data is then compressed using the deflate compression algorithm. The binary output is then encoded according to outputEncoding. Possible values for outputEncoding are "hex", "base64", "url", and "quoted-printable".

Note: The output of this method is compressed data with no Gzip file format. Use the Compress* methods to produce Gzip file format output.

Returns a zero-length WideString on failure

Full List of Charset Names

function Encode(byteData: OleVariant; encoding: WideString): WideString;

Encodes binary data to a printable string. The encoding mode is determined by encoding. It may be "base64", "hex", "quoted-printable", or "url".

Returns a zero-length WideString on failure

function ExamineFile(inGzFilename: WideString): Integer;

Determines if the inGzFilename is a Gzip formatted file. Returns 1 if it is a Gzip formatted file, otherwise returns 0.

function ExamineMemory(inGzData: OleVariant): Integer;

Determines if the in-memory bytes (inGzData) contain a Gzip formatted file. Returns 1 if it is Gzip format, otherwise returns 0.

function GetDt(): TCkDateTime;

Gets the last-modification date/time to be embedded within the .gz.

Returns nil on failure

function InflateStringENC(inString: WideString; convertFromCharset: WideString; inputEncoding: WideString): WideString;

This the reverse of DeflateStringENC.

The input string is first decoded according to inputEncoding. (Possible values for inputEncoding are "hex", "base64", "url", and "quoted-printable".) The compressed data is then inflated, and the result is then converted from convertFromCharset (if necessary) to return a string.

Returns a zero-length WideString on failure

function IsUnlocked(): Integer;

Returns 1 if the component has been unlocked.

function ReadFile(path: WideString): OleVariant;

Reads a binary file into memory and returns the byte array. Note: This method does not parse a Gzip, it is only a convenience method for reading a binary file into memory.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function SetDt(dt: TCkDateTime): Integer;

Sets the last-modification date/time to be embedded within the .gz when a Compress* method is called. If not explicitly set, the current system date/time is used.

Returns 1 for success, 0 for failure.

function UncompressBd(binDat: TChilkatBinData): Integer;

Introduced in version 9.5.0.67

In-place ungzip the contents of binDat.

Returns 1 for success, 0 for failure.

function UncompressBdAsync(binDat: TChilkatBinData): TChilkatTask;

Introduced in version 9.5.0.67

Creates an asynchronous task to call the UncompressBd method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressFile(srcPath: WideString; destPath: WideString): Integer;

Un-Gzips a .gz file. The output filename is specified by the 2nd argument and not by the filename embedded within the .gz.

Returns 1 for success, 0 for failure.

GZip Decompress File

function UncompressFileAsync(srcPath: WideString; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the UncompressFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressFileToMem(inFilename: WideString): OleVariant;

Un-Gzips a .gz file directly to memory.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function UncompressFileToMemAsync(inFilename: WideString): TChilkatTask;

Creates an asynchronous task to call the UncompressFileToMem method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressFileToString(gzFilename: WideString; charset: WideString): WideString;

Uncompresses a .gz file that contains a text file. The contents of the text file are returned as a string. The character encoding of the text file is specified by charset. Typical charsets are "iso-8859-1", "utf-8", "windows-1252", "shift_JIS", "big5", etc.

Returns a zero-length WideString on failure

List of Valid Charsets

function UncompressFileToStringAsync(gzFilename: WideString; charset: WideString): TChilkatTask;

Creates an asynchronous task to call the UncompressFileToString method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressMemory(inData: OleVariant): OleVariant;

Un-Gzips from an in-memory image of a .gz file directly into memory.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function UncompressMemoryAsync(inData: OleVariant): TChilkatTask;

Creates an asynchronous task to call the UncompressMemory method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressMemToFile(inData: OleVariant; destPath: WideString): Integer;

Un-Gzips from an in-memory image of a .gz file to a file.

Returns 1 for success, 0 for failure.

function UncompressMemToFileAsync(inData: OleVariant; destPath: WideString): TChilkatTask;

Creates an asynchronous task to call the UncompressMemToFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressString(inData: OleVariant; inCharset: WideString): WideString;

The reverse of CompressString.

The bytes in inData are uncompressed, then converted from inCharset (if necessary) to return a string.

Returns a zero-length WideString on failure

Full List of Charset Names

function UncompressStringAsync(inData: OleVariant; inCharset: WideString): TChilkatTask;

Creates an asynchronous task to call the UncompressString method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function UncompressStringENC(inStr: WideString; charset: WideString; encoding: WideString): WideString;

The same as UncompressString, except the compressed data is provided in encoded string form based on the value of encoding. The encoding can be "Base64", "modBase64", "Base32", "UU", "QP" (for quoted-printable), "URL" (for url-encoding), "Hex", "Q", "B", "url_oath", "url_rfc1738", "url_rfc2396", and "url_rfc3986".

Returns a zero-length WideString on failure

function UnlockComponent(unlockCode: WideString): Integer;

Unlocks the component allowing for the full functionality to be used.

Returns 1 for success, 0 for failure.

Diagnosing UnlockComponent Problems

UnlockComponent LastErrorText shows exact string passed to it.

Verify UnlockComponent Success w/ Purchased Unlock Code

LastErrorText Standard Information

function UnTarGz(tgzFilename: WideString; destDir: WideString; bNoAbsolute: Integer): Integer;

Unpacks a .tar.gz file. The ungzip and untar occur in streaming mode. There are no temporary files and the memory footprint is constant (and small) while untarring. bNoAbsolute may be 1 or 0. A value of 1 protects from untarring to absolute paths. (For example, imagine the trouble if the tar contains files with absolute paths beginning with /Windows/system32)

Returns 1 for success, 0 for failure.

function UnTarGzAsync(tgzFilename: WideString; destDir: WideString; bNoAbsolute: Integer): TChilkatTask;

Creates an asynchronous task to call the UnTarGz method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

function WriteFile(path: WideString; binaryData: OleVariant): Integer;

A convenience method for writing a binary byte array to a file.

Returns 1 for success, 0 for failure.

function XfdlToXml(xfldData: WideString): WideString;

Converts base64-gzip .xfdl data to a decompressed XML string. The xfldData contains the base64 data. This method returns the decoded/decompressed XML string.

Returns a zero-length WideString on failure

Events

procedure AbortCheck(ASender: TObject; out abort: Integer);

Provides the opportunity for a method call to be aborted. The AbortCheck event is fired periodically based on the value of the HeartbeatMs property. If HeartbeatMs is 0, then no AbortCheck events will fire. As an example, to fire 5 AbortCheck events per second, set the HeartbeatMs property equal to 200.

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipAbortCheck(ASender: TObject;  out abort: Integer);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnAbortCheck := gzipAbortCheck;
  // ...

procedure BinaryData(ASender: TObject; data: OleVariant; length: Integer);

Binary data provided by certain methods.

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipBinaryData(ASender: TObject;  data: OleVariant; length: Integer);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnBinaryData := gzipBinaryData;
  // ...

procedure PercentDone(ASender: TObject; pctDone: Integer; out abort: Integer);

Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This event is only fired when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For operations (Chilkat method calls) that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).

The PercentDone callback counts as an AbortCheck event. For method calls that complete quickly such that PercentDone events fire, it may be that AbortCheck events don't fire because the opportunity to abort is already provided in the PercentDone callback. For time consuming operations, where the amount of time between PercentDone callbacks are long, AbortCheck callbacks may be used to allow for the operation to be aborted in a more responsive manner.

The abort output argument provides a means for aborting the operation. Setting it to 1 will cause the method to abort and return a failed status (or whatever return value indicates failure).

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipPercentDone(ASender: TObject;  pctDone: Integer; out abort: Integer);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnPercentDone := gzipPercentDone;
  // ...

procedure ProgressInfo(ASender: TObject; const name: WideString; const value: WideString);

A general name/value event that provides information about what is happening during a method call. To find out what information is available, write code to handle this event and log the name/value pairs. Most are self-explanatory.

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipProgressInfo(ASender: TObject;  const name: WideString; const value: WideString);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnProgressInfo := gzipProgressInfo;
  // ...

procedure TaskCompleted(ASender: TObject; const task: IChilkatTask);

Called in the background thread when an asynchronous task completes.

Delphi TaskCompleted Event Callback Example

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipTaskCompleted(ASender: TObject;  const task: IChilkatTask);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnTaskCompleted := gzipTaskCompleted;
  // ...

procedure TextData(ASender: TObject; const data: WideString);

Text data provided by certain methods.

Delphi ActiveX Event callback implementation:

procedure TForm1.gzipTextData(ASender: TObject;  const data: WideString);
begin
    // Application code goes here...
end;


procedure TForm1.Button1Click(Sender: TObject);
var
  gzip: TChilkatGzip;

begin
  gzip := TChilkatGzip.Create(Self);
  gzip.OnTextData := gzipTextData;
  // ...