FlexGrid supports filtering through the ICollectionView interface. To enable filtering, set the collectionView.filter property to a function that determines objects for filtering data in the FlexGrid control. Filtering allows a user to display subsets of data out of large data sets based on the criteria defined. The CollectionView interface provided by FlexGrid provides a flexible and efficient way to filter and display the desired dataset.

The FlexGrid control lets a user perform custom filtering by adding a text box to enter a value and display a particular set of data. It also allows a user to use various options, such as BeginsWith, Contains, EndsWith, Equals, LessThan, GreaterThan etc. A user can define the filtering patterns based on their requirements, which can be a specific data or an approximate set of values.