how to transfer values from a gridview to another? If the checkbox is cheked? in vb dotnet 2010

Protected Sub BtValidCommande_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles BtValidCommande.Click
       Dim da2 As New DataSet1TableAdapters.ATTENTE_LIVRAISONTableAdapter
       Dim xnm As Double = 0
       Dim da As New DataSet1TableAdapters.DEMDETableAdapter
       Dim da1 As New DataSet1TableAdapters.E_DEMDETableAdapter
       Dim dt2 As DataSet1.DEMDEDataTable = da.GetDataDEMDE
       Dim atleastonerow As Boolean = False
       Dim i As Integer = 0
       For i = 0 To GridView1.Rows.Count - 1
           Dim cb As CheckBox = CType(GridView1.Rows(i).FindControl("checkbox1"), CheckBox)
           'Dim cb1 As CheckBox = FindControl("checkbox2")

           ' If cb.Checked Then
           If dt2.Rows.Count > 0 Then
               Dim xrow1 As DataSet1.DEMDERow = dt2.Rows(0)
               xnm = da2.QueryPROCHAINE

               For Each xrow1 In dt2.Rows
                   If cb.Checked Then
                       'da2.Insert(xnm, xrow1.SYMB, GridView2.SelectedDataKey.Values.Item(0), Now, GridView2.SelectedDataKey.Values.Item(4), GridView2.SelectedDataKey.Values.Item(1))
                       da2.Insert(xnm, GridView1.Rows(i).Cells.Item(0).Text, GridView2.SelectedDataKey.Values.Item(0), Now, GridView1.Rows(i).Cells.Item(3).Text, GridView2.SelectedDataKey.Values.Item(1))
                       da.DeleteQueryDEMDE(xrow1.SYMB)
                       da1.DeleteQueryE_DEMDEb_by_NDEM(NDEMhf.Value)
                   End If
               Next

               'End If