DataGridView does not load after selecting item from drop down list

See more:

C#

ASP.NET

HTML

DataGridView

, +

I have a drop down list which connect to sql database and display the selected data in a data grid view.

But when I select an item on the drop down list it only load but does not display the select item/items

Any one with help would appreciate that

Still a learner

Here is my codes :

ASP.NET Code

<table>
    <tr>
        <td align="left"><asp:Label id="lblShow" Text="Select Perway Status : " Font-Bold="true" runat="server"></asp:Label>
            <asp:DropDownList ID="ddlShow" runat="server" DataSourceID="SqlDataSource3"
                DataTextField="Perway_Status" DataValueField="Perway_Status" AutoPostBack="true"
                onselectedindexchanged="ddlShow_SelectedIndexChanged" >
                <asp:ListItem Text="All" Value="All" Selected="True"  Enabled="True" />
            </asp:DropDownList>
                    <asp:SqlDataSource ID="SqlDataSource3" runat="server"
                        ConnectionString="<%$ ConnectionStrings:DropDownListConnectionString %>"
                        SelectCommand="SELECT TOP 9 Station_Status_Current.Status_Time, Stations.Station_Name, Stations.Station_Lines, Sections.Section_Name, Sections.Perway_Status, Sections.Equipment_Status FROM Station_Status_Current INNER JOIN Stations ON Station_Status_Current.Station_ID = Stations.Station_ID CROSS JOIN Sections CROSS JOIN Status_Legend">
                    </asp:SqlDataSource>
        </td>
    </tr>
  </table>


                     <asp:SqlDataSource ID="SqlDataSource1" runat="server"
                        ConnectionString="<%$ ConnectionStrings:StatStressConnectionString2 %>"
                        SelectCommand="SELECT TOP 9 Station_Status_Current.Status_Time, Stations.Station_Name, Stations.Station_Lines, Sections.Section_Name, Sections.Perway_Status, Sections.Equipment_Status FROM Station_Status_Current INNER JOIN Stations ON Station_Status_Current.Station_ID = Stations.Station_ID CROSS JOIN Sections CROSS JOIN Status_Legend">
                    </asp:SqlDataSource>
    <asp:GridView ID="gvShowAll" runat="server" AutoGenerateColumns="False"
                        HorizontalAlign="Center" CellPadding="5" PageSize="20" AllowPaging="True" DataSourceID="SqlDataSource1">
        <Columns>
            <asp:BoundField DataField="Status_Time" HeaderText="Status Time"
                SortExpression="Status_Time" />
            <asp:BoundField DataField="Section_Name" HeaderText="Section Name"
                SortExpression="Section_Name" />
            <asp:BoundField DataField="Perway_Status" HeaderText="Perway Status"
                SortExpression="Perway_Status" />
            <asp:BoundField DataField="Equipment_Status" HeaderText="Equipment Status"
                SortExpression="Equipment_Status" />
            <asp:BoundField DataField="Station_Name" HeaderText="Station Name"
                SortExpression="Station_Name" />
            <asp:BoundField DataField="Station_Lines" HeaderText="Station Lines"
                SortExpression="Station_Lines" />
        </Columns>
    </asp:GridView>

</asp:Content>

Code Behind C#:

protected void ddlShow_SelectedIndexChanged(object sender, EventArgs e)
       {
           SqlDataSource3.DataBind();
           gvShowAll.DataBind();
       }
       public override void VerifyRenderingInServerForm(Control control)
       {
           return;
       }

Thanks in advance