(Delphi DLL) 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 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, BinData, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
bd: HCkBinData;
success: Boolean;
json1: HCkJsonObject;
jsonStr: PWideChar;
json2: HCkJsonObject;
bd2: HCkBinData;

begin
// First load a small JPG file..
bd := CkBinData_Create();

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

// Create JSON containing the binary data in base64 format.
json1 := CkJsonObject_Create();
CkJsonObject_UpdateBd(json1,'starfish','base64',bd);

jsonStr := CkJsonObject__emit(json1);
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 := CkJsonObject_Create();
CkJsonObject_Load(json2,jsonStr);

// Get the binary bytes.
bd2 := CkBinData_Create();
CkJsonObject_BytesOf(json2,'starfish','base64',bd2);

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

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

CkBinData_Dispose(bd);
CkJsonObject_Dispose(json1);
CkJsonObject_Dispose(json2);
CkBinData_Dispose(bd2);

end;