All examples in this topic assume that the grid is bound to a list of Composer objects, unless stated otherwise.

The following example demonstrates how to create a custom ValidationRule and apply it to a column's binding to provide binding-level validation.

XAML

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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"       xmlns:local="clr-namespace:Xceed.Wpf.Documentation">    <Grid.Resources>       <xcdg:DataGridCollectionViewSource x:Key="cvs_composers"                                          Source="{Binding Source={x:Static Application.Current},                                                            Path=Composers}"/>    </Grid.Resources>       <xcdg:DataGridControl ItemsSource="{Binding Source={StaticResource cvs_composers}}"                          UpdateSourceTrigger="RowEndingEdit">       <xcdg:DataGridControl.Columns>          <xcdg:Column FieldName="BirthYear">            <xcdg:Column.DisplayMemberBindingInfo>               <xcdg:DataGridBindingInfo Path="BirthYear">                  <xcdg:DataGridBindingInfo.ValidationRules>                     <local:YearValidationRule />                  </xcdg:DataGridBindingInfo.ValidationRules>               </xcdg:DataGridBindingInfo>            </xcdg:Column.DisplayMemberBindingInfo>         </xcdg:Column>           <xcdg:Column FieldName="DeathYear">            <xcdg:Column.DisplayMemberBindingInfo>               <xcdg:DataGridBindingInfo Path="DeathYear">                  <xcdg:DataGridBindingInfo.ValidationRules>                     <local:YearValidationRule />                  </xcdg:DataGridBindingInfo.ValidationRules>               </xcdg:DataGridBindingInfo>            </xcdg:Column.DisplayMemberBindingInfo>         </xcdg:Column>            </xcdg:DataGridControl.Columns>    </xcdg:DataGridControl>  </Grid>

Implementation of the YearValidationRule validation rule.

Visual Basic

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Imports System Imports System.Windows.Controls Imports System.Globalization Namespace Xceed.Wpf.Documentation   Public Class YearValidationRule                Inherits ValidationRule     Public Overrides Function Validate( ByVal value As Object, _                                         ByVal cultureInfo As CultureInfo ) As ValidationResult       Dim year As Integer = CInt( value )       If year > DateTime.Now.Year Then         Return New ValidationResult( False, "Chosen year cannot be greater than this year." )       End If       Return ValidationResult.ValidResult     End Function   End Class End Namespace

Implementation of the YearValidationRule validation rule.

C#

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using System; using System.Windows.Controls; using System.Globalization; namespace Xceed.Wpf.Documentation { public class YearValidationRule : ValidationRule {   public override ValidationResult Validate( object value, CultureInfo cultureInfo )   {     int year = ( int )value;     if( year > DateTime.Now.Year )       return new ValidationResult( false, "Chosen year cannot be greater than this year." );     return ValidationResult.ValidResult;   } } }

The following table provides a list of the underlying binding's properties and their immutable values.

System.Object
   Xceed.Wpf.DataGrid.DataGridBindingInfo

Supported Operating Systems: Windows Server 2003 Service Pack 1; Windows Vista; Windows XP Service Pack 2

Reference