2020-03-09

 //去掉字符串中不要的字符

    NSString *str = @"今天天气真好，探索一下NSCharacterSet";

    NSString*str1 =@"天气";

    NSMutableString *resulStr = [[NSMutableString alloc]init];

    for(inti =0; i < str.length; i ++) {

        NSString*indexStr = [strsubstringWithRange:NSMakeRange(i,1)];

        if(![str1containsString:indexStr]) {

            [resulStrappendString:indexStr];

        }

    }

    NSLog(@"常规写法:%@",resulStr);

    //利用NSCharacterSet

    NSCharacterSet *characterSet = [NSCharacterSet characterSetWithCharactersInString:@"天气"];

    NSArray *setArr = [str componentsSeparatedByCharactersInSet:characterSet];

 NSString*resultStr1 = [setArrcomponentsJoinedByString:@""];

  NSLog(@"拆分后的字符串数组--%@\n最终字符串--%@",setArr,resultStr1);