(Delphi DLL) HTTP HEAD Request

Sends an HTTP HEAD request and gets the response.

Note: The response to an HTTP HEAD request is always just the response header. The reponse body is always 0 length (thus the reason it's called a "HEAD" request..)

Note: This example requires Chilkat v11.0.0 or greater.

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, HttpResponse, Http;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
http: HCkHttp;
resp: HCkHttpResponse;
numHeaderFields: Integer;
i: Integer;

begin
success := False;

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

http := CkHttp_Create();

// If the URL uses "https://", then the connection will be TLS.
// Otherwise it will be TCP.

// A failure is when we don't get any response.  It could be a timeout, an inability to connect, etc.
// For example, a "404 Not Found" response is still a response, and thus deemed success in terms of the API..

resp := CkHttpResponse_Create();
success := CkHttp_HttpNoBody(http,'HEAD','https://example-code.com/',resp);
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// Examine the response.
Memo1.Lines.Add('Status Code = ' + IntToStr(CkHttpResponse_getStatusCode(resp)));
Memo1.Lines.Add('Status Line = ' + CkHttpResponse__statusLine(resp));
Memo1.Lines.Add('Status Text = ' + CkHttpResponse__statusText(resp));
Memo1.Lines.Add('Full Response Header:');
Memo1.Lines.Add(CkHttpResponse__header(resp));
Memo1.Lines.Add('----');
numHeaderFields := CkHttpResponse_getNumHeaderFields(resp);
Memo1.Lines.Add('Num Header Fields: ' + IntToStr(numHeaderFields));

for i := 0 to numHeaderFields - 1 do
  begin
    Memo1.Lines.Add(CkHttpResponse__getHeaderName(resp,i) + ': ' + CkHttpResponse__getHeaderValue(resp,i));
  end;

CkHttp_Dispose(http);
CkHttpResponse_Dispose(resp);

end;