要在工具提示中显示错误消息,请将其放入您的 Application.Resources 中:
<Style x:Key="textBoxInError" TargetType="{x:Type TextBox}">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<Setter Property="ToolTip"
Value="{Binding RelativeSource={x:Static RelativeSource.Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>
(示例来自http://msdn.microsoft.com/en-us/library/system.windows.controls.validation.errortemplate.aspx )
要启用/禁用按钮,您可以使用以下内容
<Button x:Name="btnOK" Content="OK" IsDefault="True" Click="btnOK_Click">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="IsEnabled" Value="false" />
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=txt1, Path=(Validation.HasError)}" Value="false" />
<Condition Binding="{Binding ElementName=txt2, Path=(Validation.HasError)}" Value="false" />
</MultiDataTrigger.Conditions>
<Setter Property="IsEnabled" Value="true" />
</MultiDataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
或者您可以实现 ICommand 并使用命令绑定。
EDIT
这是一个完整的工作示例。它显示一个带有两个文本框的窗口。当且仅当两个文本框都非空时,按钮才会启用。创建一个名为 ValidationDemo 的项目并将以下文件放入其中:
主窗口.xaml:
<Window x:Class="ValidationDemo.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="146" Width="223">
<Window.Resources>
<Style TargetType="{x:Type TextBox}">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<Grid>
<Label Content="A" Height="28" HorizontalAlignment="Left" Margin="46,7,0,0" Name="label1" VerticalAlignment="Top" />
<TextBox Name="txtA" Text="{Binding Path=TextA, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, ValidatesOnExceptions=True}" Height="23" HorizontalAlignment="Left" Margin="69,12,0,0" VerticalAlignment="Top" Width="120" />
<Label Content="B" Height="28" HorizontalAlignment="Left" Margin="46,39,0,0" Name="label2" VerticalAlignment="Top" />
<TextBox Name="txtB" Text="{Binding Path=TextB, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, ValidatesOnExceptions=True}" Height="23" HorizontalAlignment="Left" Margin="69,41,0,0" VerticalAlignment="Top" Width="120" />
<Button Name="btnOk" Content="OK" Height="23" HorizontalAlignment="Left" Margin="114,70,0,0" VerticalAlignment="Top" Width="75" Click="btnOk_Click">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="IsEnabled" Value="false" />
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=txtA, Path=(Validation.HasError)}" Value="false" />
<Condition Binding="{Binding ElementName=txtB, Path=(Validation.HasError)}" Value="false" />
</MultiDataTrigger.Conditions>
<Setter Property="IsEnabled" Value="true" />
</MultiDataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
</Grid>
</Window>
MainWindow.xaml.cs:
using System.Windows;
namespace ValidationDemo
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
private Model model = new Model();
public MainWindow()
{
InitializeComponent();
this.DataContext = this.model;
}
private void btnOk_Click(object sender, RoutedEventArgs e)
{
Application.Current.Shutdown();
}
}
}
模型.cs:
using System;
using System.ComponentModel;
namespace ValidationDemo
{
public class Model : INotifyPropertyChanged, IDataErrorInfo
{
public event PropertyChangedEventHandler PropertyChanged;
private string textA = string.Empty;
public string TextA
{
get
{
return this.textA;
}
set
{
if (this.textA != value)
{
this.textA = value;
this.OnPropertyChanged("TextA");
}
}
}
private string textB = string.Empty;
public string TextB
{
get
{
return this.textB;
}
set
{
if (this.textB != value)
{
this.textB = value;
this.OnPropertyChanged("TextB");
}
}
}
public string Error
{
get { throw new NotImplementedException(); }
}
public string this[string columnName]
{
get
{
string result = string.Empty;
switch (columnName)
{
case "TextA":
if (string.IsNullOrEmpty(this.textA))
{
result = "'A' must not be empty";
}
break;
case "TextB":
if (string.IsNullOrEmpty(this.textA))
{
result = "'B' must not be empty";
}
break;
}
return result;
}
}
protected virtual void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}