UITextField/UITextView限制字数

一,UITextFild限制字数(三步)

1,给textfild添加响应事件,类型为:UIControlEventEditingChanged

[self.nickNameFild addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];

2,实现上面的响应方法

- (void)textFieldDidChange:(UITextField *)textField{
if (textField.text.length > 20) {
textField.text = [textField.text substringToIndex:20];
}
}

3,实现textfild的代理方法

-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
//只能输入20字的第一步
NSString * toBeString = [textField.text stringByReplacingCharactersInRange:range withString:string];
if (toBeString.length > 20){
return NO;
}
return YES;
}

小结:说是三步其实 也没多少代码…

二,TextView限制字数

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
if (range.location>=300)
{
//此处提示字数超限
returnNO;
}
else
{
return YES;
}
}