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Delphi DLL

Example: Http.HttpStr method

Shows how to use the HttpStr method to send an HTTP POST request with the text of a string as the request body. The example sends the following request:
POST /echo_request_body.asp HTTP/1.1
Host: chilkatsoft.com
Accept: */*
Accept-Encoding: gzip
Content-Type: application/json
Content-Length: 26

{"greeting":"Hello World"}

Also see: Chilkat Http Default and Auto-Filled Headers

Chilkat Delphi DLL Downloads

Delphi 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;
requestBody: PWideChar;
url: PWideChar;
resp: HCkHttpResponse;

begin
success := False;

http := CkHttp_Create();
success := False;

requestBody := '{"greeting":"Hello World"}';

// This URL echoes the contents of the request body, letting us view it.
url := 'https://chilkatsoft.com/echo_request_body.asp';

// Send a POST with the contents of the string in the HTTP request body.
resp := CkHttpResponse_Create();
success := CkHttp_HttpStr(http,'POST',url,requestBody,'utf-8','application/json',resp);
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

Memo1.Lines.Add('Response Status Code: ' + IntToStr(CkHttpResponse_getStatusCode(resp)));

// Examine the request we sent.
// The LastHeader property stores the HTTP request header of the most recent request sent,
// and in this instance, the response body mirrors the request body.
Memo1.Lines.Add(CkHttp__lastHeader(http));
Memo1.Lines.Add(CkHttpResponse__bodyStr(resp));

// Output:

// POST /echo_request_body.asp HTTP/1.1
// Host: chilkatsoft.com
// Accept: */*
// Accept-Encoding: gzip
// Content-Type: application/json
// Content-Length: 26
// 
// {"greeting":"Hello World"}

CkHttp_Dispose(http);
CkHttpResponse_Dispose(resp);

end;