[Solved] CompositeFilterDescriptor.CreateFilterExpression crashing on DateTimes

[Michael]

I'm trying to use a CompositeFilterDescriptor to filter the rows in my GridView.  My rows consist of strings, a bool, and a DateTime.  It works great if I take the DateTime out, but if I leave it in, I get a "No coercion operator is defined between types 'System.DateTime' and 'System.String'." error. Is there any way to use both strings and DateTimes in my GridView and a filter?

Thanks,
Michael

[Rossen Hristov]

Hi Michael,

This indicates that you are trying to assign a string as the Value of a FilterDescriptor, whose MemberType is DateTime. Use a DateTime object, not a string and it will work.

For example,

var cfd = new CompositeFilterDescriptor();
cfd.FilterDescriptors.Add(new FilterDescriptor("DateColumn", FilterOperator.IsGreaterThan, DateTime.Now));
cfd.FilterDescriptors.Add(new FilterDescriptor("DateColumn", FilterOperator.IsLessThan, DateTime.Now.AddHours(1)));

For more info on working with filters, please read my blog posts:

Custom Filtering with RadGridView
Pre-filtering RadGridView
Pure Server-side Filtering  with RadGridView and WCF RIA Services

I hope this helps.

Best wishes,
Ross
the Telerik team