UITextView实现限制100字

placeHoderLable = [[UILabel alloc]initWithFrame:CGRectMake(3, 3, DeviceWidth-6, 40)];

//根据情况调节位置 placeHoderLable.enabled = NO;

placeHoderLable.text = @"请在这里输入您要的内容，您的预言需要经过其他用户的才能发布。";

placeHoderLable.numberOfLines=0;

placeHoderLable.font = [UIFont systemFontOfSize:12];

placeHoderLable.textColor = [UIColor lightGrayColor];

[_myTextView addSubview:placeHoderLable];

_myTextView.delegate=self;

//记得设置textview的代理 _myTextView.returnKeyType=UIReturnKeyDone;

在textview的代理方法中实现以下代码

-(void)textViewDidChange:(UITextView *)textView {

if ([_myTextView.text length] == 0) {

[placeHoderLable setHidden:NO]; }

else{ [placeHoderLable setHidden:YES]; }

}

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText: (NSString *)text {

if([text isEqualToString:@"\n"]){

[textView resignFirstResponder]; return NO; }

if (range.location>=100) {

_yuNumLable.text=@"还能输入0字"; return NO; }

else {

_yuNumLable.text=[NSString stringWithFormat:@"还能输入%lu字",100-range.location];

return YES;

}

}