Unable to cast object of type 'Kendo.Mvc.CompositeFilterDescriptor' to type 'Kendo.Mvc.FilterDescriptor'

[Alan Mosley]

I am trying to alter the meber name of a filterdescriptor but get error Unable to cast object of type 'Kendo.Mvc.CompositeFilterDescriptor' to type 'Kendo.Mvc.FilterDescriptor'  here

If request.Filters.Any(Function(y) CType(y, Kendo.Mvc.FilterDescriptor).Member.Equals("FranchiseeName")) Then

 

                     Dim filter As FilterDescriptor = CType(request.Filters.Single(Function(g) CType(g, Kendo.Mvc.FilterDescriptor).Member.Equals("FranchiseeName")), FilterDescriptor)

                     filter.Member = "Franchisee.Name"

 

 

                 End If

I don't know what the difference is or why I get this, I have done simular before without this problem.
Thanks

​

[Rosen]

Hi Alan,

There are two concreate implementation of IFilterDescriptor - the CompositeFilterDescriptor and the FilterDescriptor. CompositeFilterDescriptor class is required as the filters can be complex - multiple filters with And or Or logic. Therefore, usually the FilterDescriptors are nested within an instance of CompositeFilterDescriptor. Therefore in order to iterate over the filters you will need to conditionally navigate to through the CompositeFilterDescriptor's FilterDescriptors property. Similar to the following:

private void ChangeMemberName(IEnumerable<IFilterDescriptor> filters, string memberToSearchFor, string newMemberName)
{
    foreach (var filter in filters)
    {
        if (filter is CompositeFilterDescriptor)
        {
            ChangeMemberName(((CompositeFilterDescriptor)filter).FilterDescriptors, memberToSearchFor, newMemberName);
        }
        else if (((FilterDescriptor)filter).Member == memberToSearchFor)
        {
            ((FilterDescriptor)filter).Member = newMemberName;
        }
    }
}

public ActionResult Customers_Read([DataSourceRequest]DataSourceRequest request)
{
    if (request.Filters.Any())
    {
        ChangeMemberName(request.Filters, "FranchiseeName", "Franchisee.Name");
    }

   /*..*/
}

Regards,
Rosen
Telerik