Validation.ValidationAdornerSite Attached Property

Definition

Namespace:

System.Windows.Controls

Assembly:

PresentationFramework.dll

Gets or sets the element that appears to indicate that a validation error occurred on the bound element where this property is set.

see GetValidationAdornerSite, and SetValidationAdornerSite

see GetValidationAdornerSite, and SetValidationAdornerSite

see GetValidationAdornerSite, and SetValidationAdornerSite

Examples

The following example uses a Label as the adorner site for the validation errors that occur on items in an ItemsControl. The example sets the Validation.ValidationAdornerSite for each item container in the ItemContainerStyle to the label. The example uses the Validation.ValidationAdornerSiteFor property to get the item container that has the error and binds the Content of the Label to the first ValidationError that is reported.

<ItemsControl Name="customerList"  ItemTemplate="{StaticResource ItemTemplate}"
              ItemsSource="{Binding}">
  <ItemsControl.ItemBindingGroup>
    <BindingGroup>
      <BindingGroup.ValidationRules>
        <src:AreasMatch/>
      </BindingGroup.ValidationRules>
    </BindingGroup>
  </ItemsControl.ItemBindingGroup>
  <ItemsControl.ItemContainerStyle>
    <Style TargetType="{x:Type ContentPresenter}">
      <Setter Property="Validation.ValidationAdornerSite"
              Value="{Binding ElementName=validationErrorReport}"/>
    </Style>
  </ItemsControl.ItemContainerStyle>
</ItemsControl>

<Label Name="validationErrorReport" 
       Content="{Binding RelativeSource={RelativeSource Self}, 
       Path=(Validation.ValidationAdornerSiteFor).(Validation.Errors)[0].ErrorContent}"
       Margin="5" Foreground="Red" HorizontalAlignment="Center"/>

Remarks

The Validation.ValidationAdornerSite and Validation.ValidationAdornerSiteFor attached properties reference each other, and you can set either one. For example, suppose that a Label displays validation errors that occur on a data-bound TextBox. You can do one of the following to establish that relationship:

• Set Validation.ValidationAdornerSite for the TextBox to the Label.

• Set Validation.ValidationAdornerSiteFor for the Label to the TextBox.

• When you set one of the properties, the other property is set to the element on which you set the attached property; regardless of which of the previous options you choose, the Validation.ValidationAdornerSite for the TextBox is the Label and the ValidationAdornerSiteFor for the Label is the TextBox.

Dependency Property Information

Identifier field	ValidationAdornerSiteProperty
Metadata properties set to true	None