ทำปุ่มคลิกดูรายละเอียดใน Gridview โดยใช้ RowDataBound แต่ไม่ว่าจะคลิกปุ่มไหนก็ส่งค่าของแถวสุดท้ายหมดค่ะ

 <asp:GridView ID="SearchGrview" runat="server" AllowPaging="True" AutoGenerateColumns="False" 
   CellPadding="4" ForeColor="#333333" GridLines="None" style="text-align: left" Width="700px">
        <AlternatingRowStyle BackColor="White" ForeColor="#284775" />
        <Columns>
            <asp:TemplateField HeaderText="รหัสแผนงาน">
                <ItemTemplate>
                    <div align="center"><asp:Label ID="lblPlancode" runat="server" Text='<%# DataBinder.Eval(Container,"DataItem.Plancode") %>'></asp:Label></div>
                </ItemTemplate>
            </asp:TemplateField>

            <asp:TemplateField HeaderText="ชื่อแผนงาน">
              <ItemTemplate>
                    <asp:Label ID="lblPlanname" runat="server" Text='<%# DataBinder.Eval(Container,"DataItem.planname") %>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>

            <asp:TemplateField HeaderText="แก้ไข">
              <ItemTemplate>
                     <div align="center"><asp:ImageButton ID="btnEdit" runat="server" ImageUrl="~/Image/EditIcon.gif"></asp:ImageButton></div>
                </ItemTemplate> 
            </asp:TemplateField>
            <asp:TemplateField HeaderText="ลบ">
                <ItemTemplate>
                    <div align="center"><asp:ImageButton ID="btnDelete" runat="server" ImageUrl="~/Image/DelIcon.gif"></asp:ImageButton></div>
                </ItemTemplate> 
            </asp:TemplateField>
            <asp:TemplateField HeaderText="รายละเอียด">
                <ItemTemplate>
                     <div align="center"><asp:ImageButton ID="btnDetail" runat="server" ImageUrl="~/Image/DetailIcon.gif"></asp:ImageButton></div>
                </ItemTemplate> 
            </asp:TemplateField>
        </Columns>
    </asp:GridView>

Sub myGridView_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs) Handles SearchGrview.RowDataBound
        If e.Row.RowType = DataControlRowType.DataRow Then
            Dim DetailBtn As ImageButton = CType(e.Row.FindControl("btnDetail"), ImageButton)
            If Not IsNothing(DetailBtn) Then
                Dim planId As String = e.Row.DataItem("Plancode").ToString()
                Session("searchID") = planId
                DetailBtn.Attributes.Add("Onclick", "javascript:window.open('Default2.aspx','_blank');")
            End If
        End If
    End Sub