UITextView *textView = nil;
   /// 是否禁用限制
   textView.limit.disable = YES;
   /// 禁用emoji输入
   textView.limit.disableEmoji = YES;
   
   /// 允许最大输入100个字符(length长度大于1的,按照1个字符计算)
   textView.limit.maxCharacterNumber = 100;
   
   /// 仅输入数字
   textView.limit.onlyNumbers = YES;
   /// 仅输入中文
   textView.limit.onlyChinese = YES;
   /// 仅输入英文字母
   textView.limit.onlyLetter = YES;
   
   /// 控制输入小数样式
   textView.limit.decimaStyle = YES;
   /// 控制小数g位数
   textView.limit.decimalPlace = 2;
   
   /// 过滤输入中的输入(即数字不能输入)
   textView.limit.filterPattern = @"[0-9]+";
   /// 只允许输入输入
   textView.limit.allowPattern = @"[0-9]+";
   
   [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textViewTextDidChange:) name:UITextViewTextDidChangeNotification object:textView];
   

- (void)textViewTextDidChange:(NSNotification *)notifi {
   NSLog(@"当前输入: %d, 还可以输入: %d", textView.limit.currentCharNumber, textView.limit.canEnterCharNumber);
}