Providing Unbound Data

The following example demonstrates how to use an unbound item property to display a calculated value. In this example, the total value of the units in stock.

XAML	Copy Code
<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"> <Grid.Resources> <xcdg:DataGridCollectionViewSource x:Key="cvs_products" Source="{Binding Source={x:Static Application.Current}, Path=Products}"> <xcdg:DataGridCollectionViewSource.ItemProperties> <xcdg:DataGridUnboundItemProperty Name="TotalUnitsValue" DataType="{x:Type sys:Double}" QueryValue="DataGridUnboundItemProperty_QueryValue" /> </xcdg:DataGridCollectionViewSource.ItemProperties> </xcdg:DataGridCollectionViewSource> <local:CurrencyConverter x:Key="currencyConverter" /> </Grid.Resources> <xcdg:DataGridControl x:Name="OrdersGrid" ItemsSource="{Binding Source={StaticResource cvs_products}}"> <xcdg:DataGridControl.Columns> <xcdg:Column FieldName="TotalUnitsValue" Title="Total Inventory"> <xcdg:Column.CellContentTemplate> <DataTemplate> <TextBlock Text="{Binding Converter={StaticResource currencyConverter}}" /> </DataTemplate> </xcdg:Column.CellContentTemplate> </xcdg:Column> <xcdg:Column FieldName="Photo" Visible="False" /> </xcdg:DataGridControl.Columns> </xcdg:DataGridControl> </Grid>

XAML

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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid">

  <Grid.Resources>

     <xcdg:DataGridCollectionViewSource x:Key="cvs_products"

                                        Source="{Binding Source={x:Static Application.Current}, Path=Products}">

        <xcdg:DataGridCollectionViewSource.ItemProperties>

          <xcdg:DataGridUnboundItemProperty Name="TotalUnitsValue"

                                            DataType="{x:Type sys:Double}"

                                            QueryValue="DataGridUnboundItemProperty_QueryValue" />

        </xcdg:DataGridCollectionViewSource.ItemProperties>

     </xcdg:DataGridCollectionViewSource>

     <local:CurrencyConverter x:Key="currencyConverter" />

  </Grid.Resources>

  <xcdg:DataGridControl x:Name="OrdersGrid"

                        ItemsSource="{Binding Source={StaticResource cvs_products}}">

     <xcdg:DataGridControl.Columns>

        <xcdg:Column FieldName="TotalUnitsValue"

                     Title="Total Inventory">

           <xcdg:Column.CellContentTemplate>

              <DataTemplate>

                 <TextBlock Text="{Binding Converter={StaticResource currencyConverter}}" />

              </DataTemplate>

           </xcdg:Column.CellContentTemplate>

        </xcdg:Column>

        <xcdg:Column FieldName="Photo"

                     Visible="False" />           

     </xcdg:DataGridControl.Columns>

  </xcdg:DataGridControl>

</Grid>

The following code provides the implementation of the QueryValue event in which the unbound value will be calculated and returned.

VB.NET	Copy Code
Private Sub DataGridUnboundItemProperty_QueryValue( ByVal sender As Object, ByVal e As DataGridItemPropertyQueryValueEventArgs ) Dim System.Data.DataRowView As row = TryCast( e.Item, System.Data.DataRowView ) If Not row Is Nothing Then If( row( "UnitsInStock" ) <> DBNull.Value ) Then e.Value = CDouble( CInt( row( "UnitsInStock" ) ) * CDec( row( "UnitPrice" ) ) End If End If End Sub

VB.NET

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Private Sub DataGridUnboundItemProperty_QueryValue( ByVal sender As Object, ByVal e As DataGridItemPropertyQueryValueEventArgs )

  Dim System.Data.DataRowView As row = TryCast( e.Item, System.Data.DataRowView )

  If Not row Is Nothing Then

    If( row( "UnitsInStock" ) <> DBNull.Value ) Then

      e.Value = CDouble( CInt( row( "UnitsInStock" ) ) * CDec( row( "UnitPrice" ) )

    End If

  End If

End Sub

C#	Copy Code
private void DataGridUnboundItemProperty_QueryValue( object sender, DataGridItemPropertyQueryValueEventArgs e ) { System.Data.DataRowView row = e.Item as System.Data.DataRowView; if( row != null ) { if( row[ "UnitsInStock" ] != DBNull.Value ) { e.Value = ( double )( ( short )row[ "UnitsInStock" ] * ( decimal )row[ "UnitPrice" ] ); } } }

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private void DataGridUnboundItemProperty_QueryValue( object sender, DataGridItemPropertyQueryValueEventArgs e )

{

 System.Data.DataRowView row = e.Item as System.Data.DataRowView;

 if( row != null )

 {

   if( row[ "UnitsInStock" ] != DBNull.Value )

   {

     e.Value = ( double )( ( short )row[ "UnitsInStock" ] * ( decimal )row[ "UnitPrice" ] );

   }

 }

}