Category for get JSON string from NSDictionary, and NSData.

NSArray+JSONString.h

//
//  NSArray+JSONString.h
//  
//
//  Created by Thinh Phan on 4/26/15.
//  Copyright (c) 2015 Gennova. All rights reserved.
//

@interface NSArray (JSONString)
- (NSString *) jsonStringWithPrettyPrint:(BOOL)prettyPrint;
@end

NSArray+JSONString.m

//
//  NSArray+JSONString.m
//  
//
//  Created by Thinh Phan on 4/26/15.
//  Copyright (c) 2015 Gennova. All rights reserved.
//

@implementation NSArray (JSONString)
- (NSString*) jsonStringWithPrettyPrint:(BOOL) prettyPrint {
    NSError *error;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self
                                                       options:(NSJSONWritingOptions) (prettyPrint ? NSJSONWritingPrettyPrinted : 0)
                                                         error:&error];

    if (! jsonData) {
        NSLog(@"bv_jsonStringWithPrettyPrint: error: %@", error.localizedDescription);
        return @"[]";
    } else {
        return [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
    }
}
@end

NSDictionary+JSONString.h

//
//  NSDictionary+JSONString.h
//  
//
//  Created by Thinh Phan on 4/26/15.
//  Copyright (c) 2015 Gennova. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface NSDictionary (JSONString)
- (NSString*) jsonStringWithPrettyPrint:(BOOL) prettyPrint;
@end

NSDictionary+JSONString.m

//
//  NSDictionary+JSONString.m
//  
//
//  Created by Thinh Phan on 4/26/15.
//  Copyright (c) 2015 Gennova. All rights reserved.
//

#import "NSDictionary+JSONString.h"

@implementation NSDictionary (JSONString)

- (NSString*) jsonStringWithPrettyPrint:(BOOL) prettyPrint {
    NSError *error;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self
                                                       options:(NSJSONWritingOptions)    (prettyPrint ? NSJSONWritingPrettyPrinted : 0)
                                                         error:&error];
    
    if (! jsonData) {
        NSLog(@"jsonStringWithPrettyPrint: error: %@", error.localizedDescription);
        return @"{}";
    } else {
        return [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
    }
}
@end