カスタム フィルターの作成

Public Class GreaterThan5
   Inherits FilterOperand
   Protected Overrides ReadOnly Property DefaultDisplayName As String
      Get
         Return "Greater Than 5"
      End Get
   End Property
   Public Overrides ReadOnly Property RequiresFilteringInput As Boolean
      Get
         Return false
      End Get
   End Property
   ' ID が 5 より大きいすべての製品を返すフィルター表現を作成します。
   Public Overrides Function FilteringExpression(ByVal value As Object) As System.Linq.Expressions.Expression
      Dim expr As System.Linq.Expressions.Expression
      ((Not (product) Is Nothing) _
      AndAlso (product.ProductID > 5))
      Return expr
   End Function
End Class

public class GreaterThan5 : FilterOperand
{
   protected override string DefaultDisplayName
   {
      get
      {
         return "Greater Than 5";
      }
   }
   public override bool RequiresFilteringInput
   {
      get
      {
         return false;
      }
   }
   // ID が 5 より大きいすべての製品を返すフィルター表現を作成します。
   public override System.Linq.Expressions.Expression FilteringExpression(object value)
   {
      System.Linq.Expressions.Expression<Func<Product, bool>> expr = product => product != null && product.ProductID > 5;
      return expr;
   }
}

<UserControl.Resources>
   <DataTemplate x:Key="GreaterThanFiveIcon">
      <StackPanel>
         <TextBlock Text="&gt;5" FontWeight="Bold"></TextBlock>
      </StackPanel>
   </DataTemplate>
</UserControl.Resources>

Dim _greaterThanFiveIcon As DataTemplate = Nothing

// メンバー変数
private DataTemplate _greaterThanFiveIcon = null;

' XAML で作成したデータ テンプレートを指定します。
_greaterThanFiveIcon = CType(Me.Resources("GreaterThanFiveIcon"),DataTemplate)
Dim fcs As FilterColumnSettings = Me.MyDataGrid.Columns.DataColumns("ProductID").FilterColumnSettings
fcs.RowFilterOperands.Add(New GreaterThan5())

// XAML で作成したデータ テンプレートを指定します。
_greaterThanFiveIcon = this.Resources["GreaterThanFiveIcon"] as DataTemplate;
FilterColumnSettings fcs = this.MyDataGrid.Columns.DataColumns["ProductID"].FilterColumnSettings;
fcs.RowFilterOperands.Add(new GreaterThan5(){Icon = this._greaterThanFiveIcon});