IOS基础入门OC语言Xcode Day12笔记：Json字符串和字典互转

1、Json字符串转字典
（1）方法一

+ (NSDictionary *)dictionaryWithJsonString:(NSString *)jsonString
{
    if (jsonString == nil) {
        return nil;
    }
    NSData *jsonData = [jsonString dataUsingEncoding:NSUTF8StringEncoding];
    NSError *err;
    NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:jsonData
                                                        options:NSJSONReadingMutableContainers
                                                          error:&err];
    if(err)
    {
        NSLog(@"json解析失败：%@",err);
        return nil;
    }
    return dic;
}

(2)方法二

-(NSData *)convertToJsonData:(NSDictionary *)dict
{
    NSError *error;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dict options:NSJSONWritingPrettyPrinted error:&error];
return jsonData;
}

2、字典转Json字符串

+ (NSString *)jsonStringWithDict:(NSDictionary *)dict {
    NSError *error;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dict options:NSJSONWritingPrettyPrinted error:&error];
    NSString *jsonString;
    if (!jsonData) {
        NSLog(@"%@",error);
    }else{
        jsonString = [[NSString alloc]initWithData:jsonData encoding:NSUTF8StringEncoding];
    }
    return jsonString;
}