WPF - Validation

推荐阅读：

http://www.codeproject.com/KB/WPF/wpfvalidation.aspx

 

TextBox

 

<TextBox x:Name="theTxtbx">
    <TextBox.Style>
        <Style TargetType="TextBox">
            <Setter Property="Validation.ErrorTemplate">
                <Setter.Value>
                    <ControlTemplate>
                        <Grid>
                            <Border BorderBrush="Red" BorderThickness="1">
                                <AdornedElementPlaceholder x:Name="adornTheTxtbx"/>
                            </Border>
                            <TextBlock Foreground="Orange" FontWeight="Bold" Margin="0,25,0,0"
                                       Text="{Binding ElementName=adornTheTxtbx, Path=AdornedElement.(Validation.Errors)[0].ErrorContent}"/>
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </TextBox.Style>
    <TextBox.Text>
        <Binding Path="XXX">
            <Binding.ValidationRules>
                <ExceptionValidationRule/>
                <local:ValidateXXX/>
            </Binding.ValidationRules>
        </Binding>
    </TextBox.Text>
</TextBox>

TIP：这里在 ControlTemplate 里为 AdornedElementPlaceHolder 命名，方便在后面的 Binding 中引用；

 

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition />
        <RowDefinition />
    </Grid.RowDefinitions>
    <TextBox x:Name="txtBx">
        <TextBox.Text>
            <Binding Path="XXX">
                <Binding.ValidationRules>
                    <ExceptionValidationRule/>
                    <local:ValidateXXX/>
                </Binding.ValidationRules>
            </Binding>
        </TextBox.Text>
    </TextBox>
    <Grid Grid.Row="1">        
        <TextBlock Text="{Binding ElementName=txtBx, Path=(Validation.Errors)[0].ErrorContent}" Foreground="Red" FontWeight="Bold"/>
    </Grid>
</Grid>