Allows users to simultaneously select all or current page rows (depending on the selectAllMode).
To select rows, a user should press Ctrl + A or click the Select All check box in the selection column's header. This check box can also be used to deselect all rows. If a filter is applied, the Select All functionality affects all rows that meet filtering conditions.
If false, this property disables the Select All functionality. In this case, the check box clears selection and is hidden if no rows are selected.