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Delphi ActiveX

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 Delphi ActiveX Downloads

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
req: TChilkatHttpRequest;

begin
req := TChilkatHttpRequest.Create(Self);

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');

Memo1.Lines.Add(req.GenerateRequestText());
end;