Conversion from type 'DBNull' to type 'Boolean' is not valid.

how do u handle it in this case
Dim cholo As Boolean = CType(DataBinder.Eval(e.Row.DataItem, "morning"), Boolean)


_________this is the code if needed____________
   If e.Row.RowType = DataControlRowType.DataRow Then
            Dim lnkFile As HyperLink = CType(e.Row.FindControl("lnkFile"), HyperLink)
            Dim image1 As Image = CType(e.Row.FindControl("image1"), Image)
            Dim cholo As Boolean = CType(DataBinder.Eval(e.Row.DataItem, "morning"), Boolean)
            If cholo = True Then
                image1.visible = True
            Else
                lnkFile.Visible = True
               
            End If
        End If