NSString和JSON互转 NSString截取. enco

本人文采很差，词穷，直接上代码，简单明了，喜欢直接拿走，不送。

🌰字符串截取后四位

NSString *str2 = [carNo substringFromIndex:carNo.length - 4];//截取掉下标4之后的字符串

self.cardLastNumLB.text = [NSString stringWithFormat:@"尾号: %@",str2];

🌰判断字符串中是否含有某个字符串,例如

 [responseObject[@"err_msg"]  rangeOfString:@"登录"].location  != NSNotFound

🌰对字符串encoding

[str   stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

🌰字符串与JSON之间的转化

 方法一:

 NSData *responseData = error_data;

 NSString  * receive = [[NSString alloc]initWithData:responseData encoding:NSUTF8StringEncoding ];

🌰字符串再生成NSData

NSData *data = [receive dataUsingEncoding:NSUTF8StringEncoding];

NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];

🌰JSON转NSString

 - (NSString*)dictionaryToJson:(NSDictionary *)dic

{

     NSError *parseError = nil;

     NSData  *jsonData = [NSJSONSerialization dataWithJSONObject:dic

     options:NSJSONWritingPrettyPrinted

     error:&parseError];

     return [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];

}

🌰NSString转JSON

 -(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;

}

🌰而如果你用了SBJson的话

 NSDictionary *dic = @{@"userId":[LoginUser sharedLoginUser].userID,@"nickName":[LoginUser sharedLoginUser].userName,@"headImgUrl":[LoginUser sharedLoginUser].userIcon,@"videoId":myVideoID,@"praiseNum":@"1"};

 NSString *str=[dic JSONRepresentation];

这句话可以将dic直接转换为NSString

//encode

NSString *nickName= @"二哈";

NSString *encode = [nickName stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

如果问题解决了，请点赞给我，谢谢。。。🍎🍊🍐
原文链接：http://www.jianshu.com/p/81390e569430