UITextField

1,,

  [_OtherTextField addTarget:self action:@selector(changeTextfield) forControlEvents:UIControlEventEditingChanged];//监听数值改变；

2,,

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string//控制字符长度

 

3改变placeholder的属性

[_checkoutTxetF setValue:RGBString(@"#bbbbbb") forKeyPath:@"_placeholderLabel.textColor"];

    [_checkoutTxetF setValue:[UIFont boldSystemFontOfSize:11] forKeyPath:@"_placeholderLabel.font"];

 

//kvc的方法