iOS 将字典 数组 转换成 NSdata 或者 NSString

NSObject+JSONCategories.h

#import <Foundation/Foundation.h>

@interface NSObject (JSONCategories)

/**
* 描述：将NSArray或者NSDictionary转化为NSData
* 参数：
* 返回值：转化后的NSData
*
*/
-(NSData*)JSONData;

/**
* 描述：将NSArray或者NSDictionary转化为NSString
* 参数：
* 返回值：转化后的NSString
*
*/
-(NSString*)JSONString;

@end


NSObject+JSONCategories.m
#import "NSObject+JSONCategories.h"

@implementation NSObject (JSONCategories)

-(NSString*)JSONString;
{
NSError* error = nil;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self
options:NSJSONWritingPrettyPrinted
error:&error];

if ([jsonData length] > 0 && error == nil){
NSString *jsonString = [[NSString alloc] initWithData:jsonData
encoding:NSUTF8StringEncoding];
return [jsonString autorelease];
}else{
return nil;
}
}

-(NSData*)JSONData{
NSError* error = nil;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self
options:NSJSONWritingPrettyPrinted
error:&error];
if ([jsonData length] > 0 && error == nil){
return jsonData;
}else{
return nil;
}
}