(Delphi ActiveX) HTTPS multipart/form-data POST

Demonstrates how to send a multipart/form-data POST over HTTPS (using TLS).

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

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;
pathToFileOnDisk: WideString;
success: Integer;
fileContents: WideString;
http: TChilkatHttp;
resp: IChilkatHttpResponse;
htmlStr: WideString;

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

// This example demonstrates how to send a multipart/form-data POST that
// looks like this:

// 	POST /cgi/XXX.pl HTTP/1.0
// 	Accept: text/html
// 	Connection: Keep-Alive
// 	User-Agent: XXX/8.0.15
// 	Content-type: multipart/form-data, boundary=XXXxyxy
// 	Content-Length: 682
// 
// 	--XXXxyxy
// 	content-disposition: form-data; name="UploadAgent"
// 
// 	InterfaceVersion1.5
// 	--XXXxyxy
// 	content-disposition: form-data; name="user"
// 
// 	userValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="password"
// 
// 	passwordValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="file"
// 
// 	fileValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="data_version"
// 
// 	dataVersion
// 	--XXXxyxy
// 	content-disposition: form-data; name="content2"; filename="XXX"
// 
// 	THE FILE CONTENT GOES HERE...
// 	--XXXxyxy--
// 

// First, let's build the HTTP request object
req := TChilkatHttpRequest.Create(Self);

req.HttpVerb := 'POST';
req.Path := '/cgi/XXX.pl';

// The boundary string is automatically generated and added by Chilkat.
// The value for the boundary string doesn't matter. (As long as it's a unique string that doesn't occur elsewhere in the request.)
req.ContentType := 'multipart/form-data';

// Adding the Connection: Keep-Alive is optional.  It only makes sense if the intent is to send
// additional requests to the same domain (your-namespace-sb.accesscontrol.windows.net) within a reasonable time period.
req.AddHeader('Connection','Keep-Alive');

// --------------------------------------------------
// IMPORTANT: Never set the Content-Length header.  
// Chilkat will automatically compute the correct Content-Length and will add it.
// --------------------------------------------------

// If a specific User-Agent header field is needed, it can be added by calling AddHeader.
req.AddHeader('User-Agent','XXX/8.0.15');

// The "Accept" header, if present, tells the server what Content-Type responses will be accepted.
// In this case, we're telling the server that we'll only accept "text/html" responses, and therefore
// the server SHOULD only send a text/html response.  Technically, the Accept header is not required.
req.AddHeader('Accept','text/html');

// Add the params to the request.  Given that the Content-Type is set to "multipart/form-data", when
// Chilkat composes the request, it will put each param in it's own MIME sub-part (i.e. in it's own
// part delimited by the boundary string).
req.AddParam('UploadAgent','InterfaceVersion1.5');
req.AddParam('user','userValue');
req.AddParam('password','passwordValue');
req.AddParam('file','fileValue');
req.AddParam('data_version','dataVersion');

// The last param is the contents of a file.
// If it's a file on disk, we can add it like this:
pathToFileOnDisk := 'c:/someDir/someFile.dat';
success := req.AddFileForUpload('content2',pathToFileOnDisk);
if (success <> 1) then
  begin
    Memo1.Lines.Add(req.LastErrorText);
    Exit;
  end;

// Alternatively, if the contents of the file are in memory, perhaps in a string
// variable, the file can be added like this instead.
fileContents := 'This is the content of the file being uploaded.';
success := req.AddStringForUpload('content2','XXX',fileContents,'utf-8');

// -----------------------------------------------------------
// IMPORTANT: To duplicate the HTTP request shown above, you'll want to choose 
// either AddStringForUpload or AddFileForUpload, but not both.  It's possible to upload
// any number of files by calling AddStringForUpload and/or AddFileForUpload any number
// of times, once per file to be uploaded.  This of course assumes that the receiving
// end is programmed to receive multiple files..
// ------------------------------------------------------------

http := TChilkatHttp.Create(Self);

// The request is ready... now send it using HTTPS (which is port 443 by default).

resp := http.SynchronousRequest('www.myserver.com',443,1,req.ControlInterface);
if (http.LastMethodSuccess <> 1) then
  begin
    Memo1.Lines.Add(http.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('HTTP response status: ' + IntToStr(resp.StatusCode));

// In this case, the response would be HTML because our Accept header
// told the server to only return HTML.  The HTML is available on the BodyStr
// property of the response object:
htmlStr := resp.BodyStr;
Memo1.Lines.Add('Received:');
Memo1.Lines.Add(htmlStr);
end;