ajax - how to scroll asp.net textbox to bottom

Question

I'm building a website with text box containing log messages. the log is getting updated using AJAX.

<asp:UpdatePanel ID="UpdatePanel1" runat="server" >
    <ContentTemplate>
        <asp:TextBox ID="TextBox1" runat="server"                                 
            onload="textbox_load"
            Height="110px" 
            TextMode="MultiLine"             
            Width="100%">
        </asp:TextBox>    
    </ContentTemplate>
    <Triggers>
        <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />
    </Triggers>
</asp:UpdatePanel>

I need to scroll the text box down every time it gets updated. How?

Answer 1

Handle the Sys.WebForms.PageRequestManager.endRequest event and scroll the textbox down:

var tbox = $get('<%= TextBox1.ClientID %>');
tbox.tbox.scrollTop = tbox.scrollHeight;