Delphi DLL

QR Code Generator via api.qrserver.com REST API

See more HTTP Examples

Demonstrates how to generate a QR code using the api.qrserver.com REST API service. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Http, BinData, HttpResponse, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
http: HCkHttp;
queryParams: HCkJsonObject;
resp: HCkHttpResponse;
bd: HCkBinData;

begin
success := False;

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

http := CkHttp_Create();

// Send the following GET request to get a binary response.
// The body of the binary response contains the image data for the QR code.
// https://api.qrserver.com/v1/create-qr-code/?data=[URL-encoded-text]&size=[pixels]x[pixels]

queryParams := CkJsonObject_Create();
CkJsonObject_UpdateString(queryParams,'data','Hello World');
CkJsonObject_UpdateString(queryParams,'size','100x100');

// Get a PNG file..
// Possible formats are:
// png
// gif
// jpeg
// jpg
// svg
// eps
// Case matters.  Use lowercase.
CkJsonObject_UpdateString(queryParams,'format','png');

// Send the GET request to an endpoint.
// Chilkat will add the url-encoded query params passed in the JSON.
resp := CkHttpResponse_Create();
success := CkHttp_HttpParams(http,'GET','https://api.qrserver.com/v1/create-qr-code/',queryParams,resp);
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// Did it succeed?
if (CkHttpResponse_getStatusCode(resp) <> 200) then
  begin
    // The response body, if anything, would not be the image data, but would likely be the error text (or HTML, or whatever...)
    Memo1.Lines.Add(CkHttpResponse__bodyStr(resp));
    Memo1.Lines.Add('Response status = ' + IntToStr(CkHttpResponse_getStatusCode(resp)));
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

// Success if we get here..
// Save the binary body as the PNG file, or you can get the bytes of the PNG..
success := CkHttpResponse_SaveBodyBinary(resp,'c:/temp/qa_output/qr_code.png');

// Or get the bytes:
bd := CkBinData_Create();
CkHttpResponse_GetBodyBd(resp,bd);
// Use the bytes in bd...
// See the online reference documentation for the function to access the bytes directly.

Memo1.Lines.Add('Success.');

CkHttp_Dispose(http);
CkJsonObject_Dispose(queryParams);
CkHttpResponse_Dispose(resp);
CkBinData_Dispose(bd);

end;