Question

We have the following code in an UpdatePanel.

 <asp:UpdatePanel 
    ID="UpdatePanelSearch" 
    runat="server" 
    UpdateMode="Conditional">

    <ContentTemplate> 
        <p>Parent Search:
            <asp:TextBox ID="TextBoxSearch" runat="server" Width="207px"></asp:TextBox>
            <asp:Button ID="ButtonSearch" runat="server" Text="Search" />
        </p>
    </ContentTemplate>
 </asp:UpdatePanel>

The code in the VB file looks like this to handle clicking the Search button so a GridView will display data based on the value entered into the TextBox.

The GridView is also in a separate UpdatePanel:

Protected Sub ButtonSearch_Click(sender As Object, e As EventArgs) Handles ButtonSearch.Click

    GridViewParentsSummary.DataSource = theTableAdapter.GetData(strSearchText)
End Sub

We would like to create a trigger to update the GridView if that is the correct thing to do here.

Here is the GridView:

    <ContentTemplate> 
        <asp:GridView
            ID="GridViewParentsSummary" 
            runat="server" 
            AllowPaging="True" 
            AllowSorting="True" 
            AutoGenerateColumns="False" 
            DataKeyNames="ID" 
            PageSize="3"
            >

            <Columns>

                <asp:BoundField 
                    DataField="FatherName" 
                    HeaderText="Father's Name" 
                    SortExpression="FatherName" />

                <asp:BoundField 
                    DataField="MotherName" 
                    HeaderText="Mother's Name" 
                    SortExpression="MotherName" />

                <asp:ButtonField 
                    ButtonType="Button" 
                    CommandName="Select" 
                    Text="Select This Parent" />
            </Columns>
        </asp:GridView>
    </ContentTemplate>
</asp:UpdatePanel>

Can you show the needed code required to make the correct trigger that will refresh the GridView?

Answer 1

If the GridView is in another UpdatePanel it should also update when another UpdatePanel updates. By default, the UpdatePanel.UpdateMode property is set to Always and this will cause all UpdatePanel in page to refresh.

However, this is not always the desired behavior so many time you’ll change it to Conditional which means that the UpdatePanel will be refreshed only if one of its triggers was fired. In that case, you need to add this line in the ButtonSearch_Click method:

gridUpdatePanel.Update() 'assuming gridUpdatePanel is the UpdatePanel with the grid

for more information about the UpdateMode property look here:
http://msdn.microsoft.com/en-us/library/system.web.ui.updatepanel.updatemode.aspx