(Objective-C) 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.

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#import <CkoBinData.h>
#import <CkoJsonObject.h>
#import <NSString.h>

// First load a small JPG file..
CkoBinData *bd = [[CkoBinData alloc] init];

BOOL 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.
CkoJsonObject *json1 = [[CkoJsonObject alloc] init];
[json1 UpdateBd: @"starfish" encoding: @"base64" bd: bd];

NSString *jsonStr = [json1 Emit];
NSLog(@"%@",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..
CkoJsonObject *json2 = [[CkoJsonObject alloc] init];
[json2 Load: jsonStr];

// Get the binary bytes.
CkoBinData *bd2 = [[CkoBinData alloc] init];
[json2 BytesOf: @"starfish" encoding: @"base64" bd: bd2];

// Save to a file.
success = [bd2 WriteFile: @"qa_output/starfish20.jpg"];

NSLog(@"%@",@"Success.");