(Delphi ActiveX) Read/Write JSON with Binary Data such as JPEG Files

Demonstrates how binary files could be stored in JSON in base64 format. Creates JSON containing the contents of a JPG file, and then reads the JSON to extract the JPEG image.

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
bd: TChilkatBinData;
success: Integer;
json1: TChilkatJsonObject;
jsonStr: WideString;
json2: TChilkatJsonObject;
bd2: TChilkatBinData;

begin
// First load a small JPG file..
bd := TChilkatBinData.Create(Self);

success := bd.LoadFile('qa_data/jpg/starfish20.jpg');
// Assume success, but your code should check for success..

// Create JSON containing the binary data in base64 format.
json1 := TChilkatJsonObject.Create(Self);
json1.UpdateBd('starfish','base64',bd.ControlInterface);

jsonStr := json1.Emit();
Memo1.Lines.Add(jsonStr);

// Here's the output:
// {"starfish":"/9j/4AAQSkZJRgA ... cN2iuLFsCEbDGxQkI6RO/n//2Q=="}

// Let's create a new JSON object, load it with the above JSON, and extract the JPG image..
json2 := TChilkatJsonObject.Create(Self);
json2.Load(jsonStr);

// Get the binary bytes.
bd2 := TChilkatBinData.Create(Self);
json2.BytesOf('starfish','base64',bd2.ControlInterface);

// Save to a file.
success := bd2.WriteFile('qa_output/starfish20.jpg');

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