(Delphi DLL) URL Encoding Charset in POST Query Params

Demonstrates how to control the URL encoding charset in POST query params.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Http, StringBuilder, HttpResponse, HttpRequest;

...

procedure TForm1.Button1Click(Sender: TObject);
var
nameWin1252Encoded: PWideChar;
sb: HCkStringBuilder;
success: Boolean;
http: HCkHttp;
req: HCkHttpRequest;
resp: HCkHttpResponse;

begin
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// We have the string "MÆRSK".
nameWin1252Encoded := 'M%E6RSK';

// Note: The DecodeAndAppend method is newly added in Chilkat v9.5.0.87
sb := CkStringBuilder_Create();
success := CkStringBuilder_DecodeAndAppend(sb,nameWin1252Encoded,'url','windows-1252');

http := CkHttp_Create();

// We're setting the session log filename so we can see the exact request sent.
CkHttp_putSessionLogFilename(http,'qa_output/sessionLog.txt');

// First demonstrate a simple application/x-www-form-urlencoded POST

req := CkHttpRequest_Create();

// Set the Charset = "utf-8" to cause URL encoding to use utf-8.
CkHttpRequest_putCharset(req,'utf-8');

CkHttpRequest_AddParam(req,'name',CkStringBuilder__getAsString(sb));

resp := CkHttp_PostUrlEncoded(http,'https://www.chilkatsoft.com/something',req);
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// This is the request that is sent:
// Notice that utf-8 is used in the query param (the letter 'Æ' is %C3%A6)

// 	POST /something HTTP/1.1
// 	Host: www.chilkatsoft.com
// 	Content-Type: application/x-www-form-urlencoded
// 	Content-Length: 15
// 
// 	name=M%C3%A6RSK

CkHttpResponse_Dispose(resp);

// ---------------------------------------------------------------
// Switch to windows-1252

CkHttpRequest_putCharset(req,'windows-1252');

resp := CkHttp_PostUrlEncoded(http,'https://www.chilkatsoft.com/something',req);
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// This is the request that is sent:
// Notice that windows-1252 is used in the query param (the letter 'Æ' is %E6)

// 	POST /something HTTP/1.1
// 	Host: www.chilkatsoft.com
// 	Content-Type: application/x-www-form-urlencoded
// 	Content-Length: 12
// 
// 	name=M%E6RSK

CkHttpResponse_Dispose(resp);

// ---------------------------------------------------------------
// Let's do the same with SynchronousRequest, switching back to utf-8

CkHttpRequest_putPath(req,'/something');
CkHttpRequest_putHttpVerb(req,'POST');
CkHttpRequest_putContentType(req,'application/x-www-form-urlencoded');

CkHttpRequest_putCharset(req,'utf-8');

resp := CkHttp_SynchronousRequest(http,'www.chilkatsoft.com',443,True,req);
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// This is the request that is sent:
// Notice that utf-8 is used in the query param (the letter 'Æ' is %C3%A6)

// 	POST /something HTTP/1.1
// 	Host: www.chilkatsoft.com
// 	Content-Type: application/x-www-form-urlencoded
// 	Content-Length: 15
// 
// 	name=M%C3%A6RSK

CkHttpResponse_Dispose(resp);

// ---------------------------------------------------------------
// Let's do a PostXml where the query params are in the HTTP request start line, 
// and the Content-Type is text/xml where the body of the request is XML.

CkHttpRequest_putPath(req,'/something');
CkHttpRequest_putHttpVerb(req,'POST');
CkHttpRequest_putContentType(req,'text/xml');
success := CkHttpRequest_LoadBodyFromString(req,'<test>123</test>','utf-8');
CkHttpRequest_putCharset(req,'utf-8');

// Remember... our request object still contains the query param added in the above call to AddParam.

resp := CkHttp_SynchronousRequest(http,'www.chilkatsoft.com',443,True,req);
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// This is the request that is sent:
// Notice that utf-8 is used in the query param (the letter 'Æ' is %C3%A6)

// 	POST /something?name=M%C3%A6RSK HTTP/1.1
// 	Host: www.chilkatsoft.com
// 	Content-Type: text/xml
// 	Content-Length: 16
// 
// 	<test>123</test>

CkHttpResponse_Dispose(resp);

CkStringBuilder_Dispose(sb);
CkHttp_Dispose(http);
CkHttpRequest_Dispose(req);

end;