Serialize and Deserialize Objective-C objects into JSON

Question

I need to serialize and deserialize objective-c objects into JSON to store in CouchDB. Do people have any example code for best practice for a general solution? I looked a

Answer 1

You can easily add JSON capability to NSObject class with the help of NSDictionary,NSArray and NSJSONSerialization

Serialization:

Just see the example it will be very easy to understand.

Adding JSON Capability to NSObject Class:-

@interface JsonClassEmp : NSObject

@property(strong,nonatomic)NSString *EmpName,*EmpCode;

-(NSDictionary*)GetJsonDict;

@end

@implementation JsonClassEmp

@synthesize EmpName,EmpCode;

//Add all the properties of the class in it.
-(NSDictionary*)GetJsonDict
{
    return [NSDictionary dictionaryWithObjectsAndKeys:EmpName,@"EmpName",EmpCode,@"EmpCode", nil];
}

@end

JSON String Generator:-

In iOS 5, Apple introduced NSJSONSerialization, for parsing JSON strings so by using that we will generate JSON string.

-(NSString*)GetJSON:(id)object
{
    NSError *writeError = nil;

    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:object options:NSJSONWritingPrettyPrinted error:&writeError];

    NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];

    return jsonString;
}

Moving towards Apple’s implementation is always safer to use since you have the guarantee that it will be maintained and kept up to date.

Way to use:-

- (void)viewDidLoad
{
    [super viewDidLoad];

    JsonClassEmp *emp1=[[JsonClassEmp alloc]init];

    [emp1 setEmpName:@"Name1"];

    [emp1 setEmpCode:@"1"];

    JsonClassEmp *emp2=[[JsonClassEmp alloc]init];

    [emp2 setEmpName:@"Name2"];

    [emp2 setEmpCode:@"2"];

    //Add the NSDictionaries of the instances in NSArray
    NSArray *arrEmps_Json=@[emp1.GetJsonDict,emp2.GetJsonDict];

    NSLog(@"JSON Output: %@", [self GetJSON:arrEmps_Json]);

}

Reference

Deserialization:

It's usual way of getting the deserialized data into NSDictionary or NSArray then assign it to class properties.

I am sure using the methods and ideas used above you can serialize & deserialize complex json easily.