We are using RadGrid in SharePoint Visual Webpart with FilterType="CheckList". What we need is to be able to filter the checklist further with auto filter textbox.
1. When the filter icon is clicked, it fills with all available options (say 100 + records).
2. User enters few characters (say first 4) in the textbox and the list gets filtered with the all options starting with... (resulting in 8 records)
3. User then selects the required option for the final filter.

Please find attached image for clarification.