When a pager is used, then only the items displayed on the current page will be available. If you access RadGridView.Items collection, there are all the items just on the current page as RadGridView is not aware there are further pages.
Please note filtering is a data operation which means it is done by building and executing a LINQ query appending proper Where clause over the source collection.
That is why you can also execute such a query over the source collection directly to get all the filtered items based on the used defined filtering criteria.
var listAllFilterItems = source.Where(a => a.Name ==
All the filtering settings are available with each column's ColumnFilterDescriptor. Please check our online documentation where the filtering is explained in details.
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