How to hande checkbox event in datagrid

You need to do something as follows.

ItemCreated event of datagrid.

        If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then
            Dim cbS As CheckBox
            If Not e.Item.Cells(0).FindControl("chkSelected") Is Nothing Then
                cbS = CType(e.Item.Cells(0).FindControl("chkSelected"), CheckBox)
                AddHandler cbS.CheckedChanged, AddressOf checkBox_CheckedChanged
            End If
            cbS = nothing
        End If

Private Sub checkBox_CheckedChanged()
 
End Sub