一、属性
//自定义的textview
@property (weak, nonatomic) IBOutlet UITextView *textview; //添加一个bool类型的属性 @property (nonatomic, assign) BOOL isNameTextFieldEnbable;二、监听通知、并初始化BOOL值
//UITextView的监听方法
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textchange:) name:UITextViewTextDidChangeNotification object:nil]; //初始化为YES，让textView开始输入有反应 self.isNameTextFieldEnbable = YES;三、监听方法
/** 监听方法 */
-(void)textchange:(NSNotification *)note{
//最大字数
static const NSInteger Max_Num_TextView = 5; //监听开始默认YES self.isNameTextFieldEnbable = YES; //当前输入语言状态 UITextInputMode *mode = (UITextInputMode *)[UITextInputMode activeInputModes][0]; NSString *lang = mode.primaryLanguage; //汉字 if ([lang isEqualToString:@"zh-Hans"]) { UITextRange *selectedRange = [self.textview markedTextRange]; //高亮状态的start位置 UITextPosition *position = [self.textview positionFromPosition:selectedRange.start offset:0]; //没有高亮状态，即每次截取要在文字确认之后 if (!position) { if (self.textview.text.length > Max_Num_TextView) { self.textview.text = [self.textview.text substringToIndex:Max_Num_TextView]; self.isNameTextFieldEnbable = NO; } } } //非汉字状态 else{ if (self.textview.text.length > Max_Num_TextView) { self.textview.text = [self.textview.text substringToIndex:Max_Num_TextView]; self.isNameTextFieldEnbable = NO; } } }四、TextView的代理方法
//是否允许键盘输入
-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{ //返回删除键 if ([text isEqualToString:@""]) { return YES; }else{ return _isNameTextFieldEnbable; } }