FilterDescriptorCollection using OR

[Joel Palmer]

I have a DataGrid that needs to be filtered programatically.  I populate the dependency grid with a ItemsSource with all my data in it.  When I select an item in a parent grid, I want this grid to filter showing the one or many dependency items. 

So, I'd figured out I can clear the FilterDescriptorCollection and add items to it in using this syntax.  Note FilterSettings = FilterDescriptorCollection:

aggregationGridView.FilterSettings.Clear();
foreach (AggregateDD child in aggregate.ChildList)
{
    FilterDescriptor filter = new FilterDescriptor(
         "AggregateID", FilterOperator.IsEqualTo, child.AggregateID);
    aggregationGridView.FilterSettings.Add(filter);
}

However, this seems to write a query that as AND instead of OR.  This is more the query I'd like to run:

( (AggregateID IsEqualTo 385 MC) OR (AggregateID IsEqualTo 386 MC) OR (AggregateID IsEqualTo 387 MC) OR (AggregateID IsEqualTo 388 MC) )

How do I add a new FilterDescriptor to the FilterDescriptorCollection as an OR?

Thanks for your help.

[Rossen Hristov]

Hello Joel Palmer,

There is a special filter descriptor called CompositeFilterDescriptor. It combines one or more "normal"  filter descriptors with a logical operator of AND/OR. So you can do the following:

var compositeFilter = new CompositeFilterDescriptor();
compositeFilter.LogicalOperator = FilterCompositionLogicalOperator.Or;
foreach (AggregateDD child in aggregate.ChildList)
{
    FilterDescriptor filter = new FilterDescriptor(
         "AggregateID", FilterOperator.IsEqualTo, child.AggregateID);
    compositeFilter.FilterDescriptors.Add(filter);
}
aggregationGridView.FilterSettings.Add(compositeFilter);

With the help of this CompositeFilterDescriptor you can create N-level hierarchies of filters, i.e. trees of filters.

I hope this helps. Let me know if there are problems.

All the best,
Ross
the Telerik team

[gans]

Is the FilterSettings Deprecated? I don't see it in the RadTreeListView and also in RadGridView.