Using logical operator OR between columns for filtering

[bohebolo]

Maybe this is not a common case, but we really need to achieve this.
I'm creating a custom control that use RadGridView as one of it's part.
Our control need filtering capability, and I'm doing it this way:

foreach (GridViewColumn column in _gridView.Columns)

{

    if ((column as GridViewBoundColumnBase).DataType == typeof(string))

    {

        IColumnFilterDescriptor columnDescriptor = column.ColumnFilterDescriptor;

        columnDescriptor.SuspendNotifications();

        columnDescriptor.FieldFilter.Filter1.Operator = FilterOperator.Contains;

        columnDescriptor.FieldFilter.Filter1.Value = keyword;

        columnDescriptor.ResumeNotifications();

    }

}

 
My question is how to create the filter that uses logical operator OR between columns?
Something like this:
Where column1 = xxx OR column2 = xxx

thanks

[bohebolo]

Maybe my question wasn't clear enough so let me re-phrase it.
I am creating a custom ComboBox, that uses RadGridView as it's popup part.
What I want to achieve is: when user type inside the ComboBox's textbox, then the popup will be shown up with RadGridView items already filtered based on textbox's text.
Everything are working well, except I don't know how to do filter in RadGridView that uses logical "OR" operator between it's columns.

Please take a look on attached picture.
I want to filter RadGridView items with something like this: WHERE roleCode='XX'  OR  roleName='XX'
What I got now by using above code is: WHERE roleCode='XX'  AND  roleName='XX'

How to filter RadGridView items using that logical "OR" operator ?
Any comments, suggestion, or references will be appreciated.

thanks

[bohebolo]

Any idea anyone?
Does someone from Telerik can confirm if it's possible to achieve this or not?
If the answer is not, I can create an event and let the developer that uses the combobox (my custom control) to create a handler and do the filter with their own way.
But somehow I don't think it is a correct way, since it will give them more job to be done.

PS: I'm racing with the deadline, and now stuck only on this matter.
Please let me know if my question wasn't clear enough.

thanks & regards

[bohebolo]

After digging Telerik online help, finally I found the solution.

if (_gridView.FilterDescriptors.Count > 0)
    _gridView.FilterDescriptors.Clear();

CompositeFilterDescriptor mainCompositeDescriptor = new CompositeFilterDescriptor();
mainCompositeDescriptor.LogicalOperator = FilterCompositionLogicalOperator.Or;

foreach (GridViewColumn column in _gridView.Columns)
{
    if ((column as GridViewBoundColumnBase).DataType == typeof(string))
    {
        FilterDescriptor descriptor = new FilterDescriptor();
        descriptor.Member = column.UniqueName;
        descriptor.Operator = FilterOperator.Contains;
        descriptor.Value = keyword;
        mainCompositeDescriptor.FilterDescriptors.Add(descriptor);
    }
}

_gridView.FilterDescriptors.Add(mainCompositeDescriptor);