NSJSONSerialization（category）的一个扩展类
.h文件
//
// NSJSONSerialization+Manage.h
// SVPullToRefreshDemo
//
// Created by Fuer on 14-7-4.
// Copyright (c) 2014年 Home. All rights reserved.
//
#import <Foundation/Foundation.h>
/**
* The domain for NSErrors generated by the NSJSONSerialization+UAAdditions methods.
*/
extern NSString * const UAJSONSerializationErrorDomain;
NS_ENUM(NSInteger, UAJSONSerializationErrorCode) {
UAJSONSerializationErrorCodeInvalidObject
};
@interface NSJSONSerialization (Manage)
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @return NSString formatted as JSON, or nil if an error occurs
* @note Writing JSON strings with this method defaults to no NSJSONWritingOptions, and does not accept fragments.
*/
+ (NSString *)stringWithObject:(id)jsonObject;
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @param error An NSError pointer for storing errors, if applicable.
* @return NSString formatted as JSON, or nil if an error occurs
* @note Writing JSON strings with this method defaults to no NSJSONWritingOptions, and does not accept fragments.
*/
+ (NSString *)stringWithObject:(id)jsonObject error:(NSError **)error;
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @param acceptingFragments `YES` if objects representing JSON value fragments are acceptable, `NO` otherwise.
* @return NSString formatted as JSON, or nil if an error occurs.
* @note Writing JSON strings with this method defaults to no NSJSONWritingOptions.
*/
+ (NSString *)stringWithObject:(id)jsonObject acceptingFragments:(BOOL)acceptingFragments;
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @param acceptingFragments `YES` if objects representing JSON value fragments are acceptable, `NO` otherwise.
* @param error An NSError pointer for storing errors, if applicable.
* @return NSString formatted as JSON, or nil if an error occurs.
* @note Writing JSON strings with this method defaults to no NSJSONWritingOptions.
*/
+ (NSString *)stringWithObject:(id)jsonObject acceptingFragments:(BOOL)acceptingFragments error:(NSError **)error;
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @param opt NSJSONWritingOptions options
* @return NSString formatted as JSON, or nil if an error occurs
*/
+ (NSString *)stringWithObject:(id)jsonObject options:(NSJSONWritingOptions)opt;
/**
* Converts a Foundation object to a JSON formatted NSString
* @param jsonObject Foundation object to convert
* @param opt NSJSONWritingOptions options
* @param error An NSError pointer for storing errors, if applicable.
* @return NSString formatted as JSON, or nil if an error occurs
*/
+ (NSString *)stringWithObject:(id)jsonObject options:(NSJSONWritingOptions)opt error:(NSError **)error;
/**
* Create a Foundation object from JSON string
* @param jsonString the JSON NSString to convert
* @return A Foundation object, or nil if an error occurs.
* @note Creating objects with this method defaults to NSJSONReadingMutableContainers options.
*/
+ (id)objectWithString:(NSString *)jsonString;
/**
* Create a Foundation object from JSON string
* @param jsonString the JSON NSString to convert
* @param opt NSJSONReadingOptions
* @return A Foundation object, or nil if an error occurs.
*/
+ (id)objectWithString:(NSString *)jsonString options:(NSJSONReadingOptions)opt;
/**
* Create a Foundation object from JSON string
* @param jsonString the JSON NSString to convert
* @param opt NSJSONReadingOptions
* @param error An NSError pointer for storing errors, if applicable.
* @return A Foundation object, or nil if an error occurs.
*/
+ (id)objectWithString:(NSString *)jsonString options:(NSJSONReadingOptions)opt error:(NSError **)error;
@end
.m文件
//
// NSJSONSerialization+Manage.m
// SVPullToRefreshDemo
//
// Created by Fuer on 14-7-4.
// Copyright (c) 2014年 Home. All rights reserved.
//
#import "NSJSONSerialization+Manage.h"
@implementation NSJSONSerialization (Manage)
NSString * const UAJSONSerializationErrorDomain = @"com.urbanairship.json_serialization";
+ (NSString *)stringWithObject:(id)jsonObject {
return [NSJSONSerialization stringWithObject:jsonObject options:0 acceptingFragments:NO error:nil];
}
+ (NSString *)stringWithObject:(id)jsonObject error:(NSError **)error {
return [NSJSONSerialization stringWithObject:jsonObject options:0 acceptingFragments:NO error:error];
}
+ (NSString *)stringWithObject:(id)jsonObject options:(NSJSONWritingOptions)opt {
return [NSJSONSerialization stringWithObject:jsonObject options:opt acceptingFragments:NO error:nil];
}
+ (NSString *)stringWithObject:(id)jsonObject options:(NSJSONWritingOptions)opt error:(NSError **)error {
return [NSJSONSerialization stringWithObject:jsonObject options:opt acceptingFragments:NO error:error];
}
+ (NSString *)stringWithObject:(id)jsonObject acceptingFragments:(BOOL)acceptingFragments {
return [NSJSONSerialization stringWithObject:jsonObject options:0 acceptingFragments:acceptingFragments error:nil];
}
+ (NSString *)stringWithObject:(id)jsonObject acceptingFragments:(BOOL)acceptingFragments error:(NSError **)error {
return [NSJSONSerialization stringWithObject:jsonObject options:0 acceptingFragments:acceptingFragments error:error];
}
+ (NSString *)stringWithObject:(id)jsonObject
options:(NSJSONWritingOptions)opt
acceptingFragments:(BOOL)acceptingFragments
error:(NSError **)error {
if (!jsonObject) {
return nil;
}
if (!acceptingFragments ||
([jsonObject isKindOfClass:[NSArray class]] || [jsonObject isKindOfClass:[NSDictionary class]])) {
if (![NSJSONSerialization isValidJSONObject:jsonObject]) {
if (error) {
NSString *msg = [NSString stringWithFormat:@"Attempted to serialize invalid object: %@", jsonObject];
NSDictionary *info = @{NSLocalizedDescriptionKey:msg};
*error = [NSError errorWithDomain:UAJSONSerializationErrorDomain
code:UAJSONSerializationErrorCodeInvalidObject
userInfo:info];
}
return nil;
}
NSData *data = [NSJSONSerialization dataWithJSONObject:jsonObject
options:opt
error:error];
return [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
} else {
//this is a dirty hack but it works well. while NSJSONSerialization doesn't allow writing of
//fragments, if we serialize the value in an array without pretty printing, and remove the
//surrounding bracket characters, we get the equivalent result.
NSString *arrayString = [self stringWithObject:@[jsonObject] options:0 acceptingFragments:NO error:error];
return [arrayString substringWithRange:NSMakeRange(1, arrayString.length-2)];
}
}
+ (id)objectWithString:(NSString *)jsonString {
return [self objectWithString:jsonString options:NSJSONReadingMutableContainers];
}
+ (id)objectWithString:(NSString *)jsonString options:(NSJSONReadingOptions)opt {
return [self objectWithString:jsonString options:opt error:nil];
}
+ (id)objectWithString:(NSString *)jsonString options:(NSJSONReadingOptions)opt error:(NSError **)error {
if (!jsonString) {
return nil;
}
return [NSJSONSerialization JSONObjectWithData: [jsonString dataUsingEncoding:NSUTF8StringEncoding]
options: opt
error: error];
}
@end
option參数说明.
enum {
NSJSONReadingMutableContainers = (1UL << 0), //返回的容器是可变类型的（Array和Dictionary）
NSJSONReadingMutableLeaves = (1UL << 1), //返回的叶子NSString是可变类型的；
NSJSONReadingAllowFragments = (1UL << 2) //同意顶层的界面不是NSArray或NSDictionary；
};
typedef NSUInteger NSJSONReadingOptions;
