Private Sub dataGridView1_CellValueChanged(ByVal sender As Object, ByVal e As DataGridViewCellEventArgs)
Dim isSelect As Boolean = If(TryCast(dataGridView1(4, e.RowIndex).Value, Boolean?), False)
If isSelect Then
Dim row = Me.dataGridView1.Rows(e.RowIndex)
row.DefaultCellStyle.BackColor = Color.Red
End If
End Sub