Delphi DLL

Read/Write JSON with Binary Data such as JPEG Files

See more JSON Examples

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. Delphi 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
success: Boolean;
bd: HCkBinData;
json1: HCkJsonObject;
jsonStr: PWideChar;
json2: HCkJsonObject;
bd2: HCkBinData;

begin
success := False;

// 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;