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Lazarus Pascal

Add Parameters to Multipart Form-Data POSTs

Parameters (name=value) can be added to multipart/form-data POSTs (such as for file uploads) by using the AddParam method. This example sends the following HTTP POST
POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=------------010201080703010401070605
Host: domain
Content-Length: 560

--------------010201080703010401070605
Content-Disposition: form-data; name="name"

Joe
--------------010201080703010401070605
Content-Disposition: form-data; name="age"

25
--------------010201080703010401070605
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--------------010201080703010401070605
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--------------010201080703010401070605--

Chilkat Lazarus Pascal Downloads

Lazarus Pascal
program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.HttpRequest;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  req: THttpRequest;

begin
  req := THttpRequest.Create;

  req.HttpVerb := 'POST';
  req.Path := '/something';
  req.ContentType := 'multipart/form-data';

  req.AddParam('name','Joe');
  req.AddParam('age','25');

  req.AddStringForUpload('fileA','fileA.txt','This is the contents of file A','utf-8');
  req.AddStringForUpload('fileB','fileB.txt','This is the contents of file B','utf-8');

  WriteLn(req.GenerateRequestText());


  req.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.