ถามเรื่อง Error การเพิ่มข้อมูลจาก DataGridView1 ไปยัง DataGridView2 ที่อยู่อีกหน้าครับ

    Private Sub bt_Cancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bt_Cancel.Click
        lb_empFname.Text = login.Emp_Fname
        lb_empLname.Text = login.Emp_Lname
        Clear()
        Control_bt()
        Control_child_bt()
        Disabled_Display()
        dt_saleDate.ResetText()
        bt_Add.Enabled = True
        bt_Back.Enabled = True
        bt_ViewDetail.Enabled = True
        DataGridView1.Enabled = False

        If DataGridView2.Rows.Count = 0 Then
            Exit Sub
        Else
            DataGridView2.DataSource.Clear()
        End If
    End Sub

'****************************************************************************************************
        'เลือกสุนัขเเล้วส่งไปหน้า sale 
        '****************************************************************************************************
        For i = 0 To DataGridView1.Rows.Count - 1
            If DataGridView1.Rows(i).Selected Then
                Dim j As Integer = Sale.DataGridView2.Rows.Add()
                Sale.DataGridView2.Rows(j).Cells(0).Value = DataGridView1.Rows(i).Cells(0).Value
                Sale.DataGridView2.Rows(j).Cells(1).Value = DataGridView1.Rows(i).Cells(1).Value
                Sale.DataGridView2.Rows(j).Cells(2).Value = DataGridView1.Rows(i).Cells(2).Value
                Sale.DataGridView2.Rows(j).Cells(3).Value = DataGridView1.Rows(i).Cells(3).Value
                Sale.DataGridView2.Rows(j).Cells(4).Value = DataGridView1.Rows(i).Cells(4).Value
            End If
        Next