字典(NSDictionary)和JSON字符串(NSString)之间互转

字典转Json字符串

-(NSString *)convertToJsonData:(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];

    }

NSMutableString *mutStr = [NSMutableString stringWithString:jsonString];

NSRange range = {0,jsonString.length};

//去掉字符串中的空格

[mutStr replaceOccurrencesOfString:@" " withString:@"" options:NSLiteralSearch range:range];

NSRange range2 = {0,mutStr.length};

//去掉字符串中的换行符

[mutStr replaceOccurrencesOfString:@"\n" withString:@"" options:NSLiteralSearch range:range2];

return mutStr;

}

JSON字符串转化为字典

+ (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;
}