QueryDistinctValueEventArgs Class

Provides information on a distinct value extracted from the underlying data source and allows a new one to be provided in its stead.

Syntax

Visual Basic
C#

'Declaration
 
Public Class QueryDistinctValueEventArgs 
   Inherits System.EventArgs

'Usage
 
Dim instance As QueryDistinctValueEventArgs

public class QueryDistinctValueEventArgs : System.EventArgs

Example

All examples in this topic assume that the grid is bound to the Orders table of the Northwind database, unless stated otherwise.

The following example demonstrates how to provide custom distinct values that will display the only the month in columns that display DateTime values and that will filter according to a value range for a decimal column.

XAML

<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid">
  <Grid.Resources>
     <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"
                                        Source="{Binding Source={x:Static Application.Current}, Path=Orders}"
                                        AutoFilterMode="And"
                                        DefaultCalculateDistinctValues="False">
        <xcdg:DataGridCollectionViewSource.ItemProperties>

          <xcdg:DataGridItemProperty Name="OrderDate"
                                     QueryDistinctValue="DataGridItemProperty_QueryDistinctValue_Date"
                                     CalculateDistinctValues="True"/>
          <xcdg:DataGridItemProperty Name="RequiredDate"
                                     QueryDistinctValue="DataGridItemProperty_QueryDistinctValue_Date"
                                     CalculateDistinctValues="True" />
          <xcdg:DataGridItemProperty Name="ShippedDate"
                                     QueryDistinctValue="DataGridItemProperty_QueryDistinctValue_Date"
                                     CalculateDistinctValues="True" />
          <xcdg:DataGridItemProperty Name="Freight"
                                     QueryDistinctValue="DataGridItemProperty_QueryDistinctValue_Range"
                                     CalculateDistinctValues="True" />
        </xcdg:DataGridCollectionViewSource.ItemProperties>
     </xcdg:DataGridCollectionViewSource>
   
  </Grid.Resources>
  <xcdg:DataGridControl x:Name="OrdersGrid"
                        ItemsSource="{Binding Source={StaticResource cvs_orders}}"/>
</Grid>

Visual Basic

Private Sub DataGridItemProperty_QueryDistinctValue_Date( ByVal sender As Object, ByVal e As QueryDistinctValueEventArgs )
  If TypeOf e.DataSourceValue Is DateTime Then
    e.DistinctValue = CDate( e.DataSourceValue ).ToString( "MMMM" )
  End If
End Sub

Private Sub DataGridItemProperty_QueryDistinctValue_Range( ByVal sender As Object, ByVal e As QueryDistinctValueEventArgs )
  If TypeOf e.DataSourceValue Is Decimal Then
    Dim value As Decimal = CDec( e.DataSourceValue )
    If value <= 100 Then
      e.DistinctValue = "0 - 100"
    ElseIf( value > 100 And value <= 500 ) Then
      e.DistinctValue = "101 - 500"
    Else
      e.DistinctValue = "500+"
    End If
  End If
End Sub

private void DataGridItemProperty_QueryDistinctValue_Date( object sender, QueryDistinctValueEventArgs e )
{
 if( e.DataSourceValue is DateTime )
 {
   e.DistinctValue = ( ( DateTime )e.DataSourceValue ).ToString( "MMMM" );
 }
}

private void DataGridItemProperty_QueryDistinctValue_Range( object sender, QueryDistinctValueEventArgs e )
{
 if( e.DataSourceValue is decimal )
 {
   decimal value = ( decimal )e.DataSourceValue;
   if( value <= 100 )
   {
     e.DistinctValue = "0 - 100";
   }
   else if( value > 100 && value <= 500 )
   {
     e.DistinctValue = "101 - 500";
   }
   else
   {
     e.DistinctValue = "500+";
   }
 }
}

Inheritance Hierarchy

System.Object
System.EventArgs
Xceed.Wpf.DataGrid.QueryDistinctValueEventArgs

Requirements

Target Platforms: Windows 11, Windows 10, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

QueryDistinctValueEventArgs Members
Xceed.Wpf.DataGrid Namespace