Cannot sort numerical data column

[Søren]

I have a RadGridView with the following properties:

telerik:RadGridView x:Name="SearchResult_DataGrid"
 Grid.Row="2"
 AutoGenerateColumns="False"
 IsReadOnly="True"
 RowIndicatorVisibility="Collapsed"
 CanUserFreezeColumns="False"
 CanUserResizeColumns="False"
 DataContext="{Binding}"
 ItemsSource="{Binding Path=Data}"
 SelectedItem="{Binding Path=SelectedItem, Mode=TwoWay}"
 MouseRightButtonDown="SearchResult_DataGrid_MouseRightButtonDown"
 ShowGroupPanel="False" >
<telerik:RadGridView.Columns>
 <telerik:GridViewDataColumn DataMemberBinding="{Binding Date}" Header="Date"/>
 <telerik:GridViewDataColumn Header="Week" DataMemberBinding="{Binding Week}" />
</telerik:RadGridView.Columns>
</telerik:RadGridView>

When I try to sort by week, I get the "classic" string-sort problem, e.g.

10
11
4
42
7

I've tried setting the DataType programatically:

var column = SearchResult_DataGrid.Columns["Week"] as Telerik.Windows.Controls.GridViewBoundColumnBase;
if (column != null)
{
  column.DataType = typeof(int);
}

But it doesn't help.
I've searched high and low in the forum and stumbled upon someone mentioning a numerical column, but I can't find that in the documentation. It seems a bit overkill to make custom sorting on a column that contain integers, so I would very much like to find a solution to this problem, since I have other columns with the same problem.

So - how do I sort a column based on numerical values?

I'm using the Q3 2011 version

Best regards
Søren Hansen

[Vlad]

Hi,

 Changing DataType property of the grid column will not change your underlying data data type. You cannot sort strings as numeric!

Regards,
Vlad
the Telerik team

[Søren]

Thank you for the quick response!

I've changed the underlying data type to int, and now it sorts as expected. The reason it was a string before, was to enable error messages, which has now been moved.

/Søren