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

1. 字典转Json字符串

// 字典转json字符串方法

-(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; 
 }

2. 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;
    }