在wpf对话框窗口中,我有一个启用和禁用文本框的复选框。文本框的ValidatesOnDataErrors设置为True。通过IDataErrorInfo我只检查此文本框的值,如果选中该复选框。
我的问题是,如果用户选中复选框,则没有对文本框执行新的验证,因此我不会得到指示错误的红框。
这里的示例是一个小样本:
<Window x:Class="Validation.ValidationWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="ValidationWindow" Height="300" Width="300">
<DockPanel LastChildFill="False">
<CheckBox DockPanel.Dock="Top" IsChecked="{Binding InputAllowed}">Input allowed</CheckBox>
<StackPanel DockPanel.Dock="Top" Orientation="Horizontal">
<Label>InputValue</Label>
<TextBox Text="{Binding InputValue, ValidatesOnDataErrors=True}" IsEnabled="{Binding InputAllowed}" Width="50"/>
</StackPanel>
<StackPanel DockPanel.Dock="Top" Orientation="Horizontal">
<Label>InputValue2</Label>
<TextBox Text="{Binding InputValue2, ValidatesOnDataErrors=True}" Width="50"/>
</StackPanel>
<Button DockPanel.Dock="Bottom" Click="OnOk">Ok</Button>
</DockPanel>
</Window>
代码背后的代码:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
namespace Validation
{
/// <summary>
/// Interaction logic for ValidationWindow.xaml
/// </summary>
public partial class ValidationWindow : Window, IDataErrorInfo
{
public bool InputAllowed
{
get { return (bool)GetValue(InputAllowedProperty); }
set { SetValue(InputAllowedProperty, value); }
}
public static readonly DependencyProperty InputAllowedProperty =
DependencyProperty.Register("InputAllowed", typeof(bool), typeof(ValidationWindow), new PropertyMetadata(false));
public int InputValue
{
get { return (int)GetValue(InputValueProperty); }
set { SetValue(InputValueProperty, value); }
}
public static readonly DependencyProperty InputValueProperty =
DependencyProperty.Register("InputValue", typeof(int), typeof(ValidationWindow), new PropertyMetadata(0));
public int InputValue2
{
get { return (int)GetValue(InputValue2Property); }
set { SetValue(InputValue2Property, value); }
}
public static readonly DependencyProperty InputValue2Property =
DependencyProperty.Register("InputValue2", typeof(int), typeof(ValidationWindow), new PropertyMetadata(0));
public ValidationWindow()
{
InitializeComponent();
DataContext = this;
}
private void OnOk(object sender, RoutedEventArgs e)
{
string msg = Error;
if(!string.IsNullOrEmpty(Error))
{
MessageBox.Show(Error);
return;
}
DialogResult = true;
}
#region IDataErrorInfo Members
public string Error
{
get { return ((IDataErrorInfo)this)[null]; }
}
public string this[string columnName]
{
get
{
string msg = string.Empty;
if(string.IsNullOrEmpty(columnName))
{
msg += ((IDataErrorInfo)this)["InputValue"];
msg += ((IDataErrorInfo)this)["InputValue2"];
}
else
{
switch(columnName)
{
case "InputValue":
if(InputAllowed)
{
if(InputValue <= 0)
{
msg += "InputValue must be greater that 0!";
}
}
break;
case "InputValue2":
if(InputValue2 <= 0)
{
msg += "InputValue2 must be greater that 0!";
}
break;
}
}
return msg;
}
}
#endregion
}
}
答案 0 :(得分:2)
我们一直在使用此方法在编程更改文本后强制进行验证,如果您在响应复选框的事件时调用它,也应该正常工作:
var binding = someTextBox.GetBindingExpression( TextBox.TextProperty );
if( binding == null )
return;
binding.UpdateSource();
答案 1 :(得分:1)
与stijn的解决方案没有实际区别,但因为我们都有点懒惰:
public static class DependencyPropertyExtensions
{
public static bool UpdateSource(this FrameworkElement source, DependencyProperty property)
{
var binding = source.GetBindingExpression(property);
if (binding != null)
{
binding.UpdateSource();
return true;
}
return false;
}
}