//中文转成utf8

    NSString *utf8 = [@"今晚打老虎"

                     stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    

    //utf8转成中文

    NSString *zhongwen = [utf8 stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    

    NSLog(@"utf8->%@",utf8);

    NSLog(@"zhongwen->%@",zhongwen);