字符串的替换

替换字符串

NSMutableString *str = [NSMutableString stringWithFormat:@"13233675678"];
    [str replaceCharactersInRange:NSMakeRange(3, 4) withString:@"****"];
    NSString *str_mobile = [NSString stringWithFormat:@"%@",str];
    NSLog(@"%@",str_mobile);