OnTextChanged loses focus when AutoPostBack is true

Question

I have a ASP.Net webform that has several textboxes. Some of the textboxes have an OnTextChanged event with AutoPostBack set to true.

When the user enters some text and leaves the textbox, I want some code to run. This part works fine.

The problem is that if a user enters some text, then clicks or tabs to another textbox, the OnTextChanged of the current textbox event fires fine but the textbox that the user clicked on does not keep focus. This causes problems because the user thinks they are on the next textbox but they aren't. And no object seems to have the focus.

Is there anything that can be done to make the next object keep focus while the OnTextChanged event of the current textbox fires?

Mt. Schneiders Mt. Schneiders · Accepted Answer · 2013-05-31T22:24:13

One option is to use <asp:UpdatePanel> Control.

Facts about using it:

The postback request would be made via AJAX.
It would not recreate the whole page HTML.
When the UpdatePanel updates, it replaces the DIV innerHTML, that would make the textbox lose focus (bad point).
To maintain the focus, you would have to avoid the UpdatePanel from updating when the textbox posts back.
You can avoid the update by setting the UpdateMode and ChildrenAsTriggers properties.

Here is an example:

<asp:UpdatePanel ID="uppTextboxes" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="false">
    <ContentTemplate>
        <asp:TextBox ID="txb1" runat="server" AutoPostBack="true" OnTextChanged="txb1_OnTextChanged" />
        <asp:TextBox ID="txb2" runat="server" />
    </ContentTemplate>
</asp:UpdatePanel>

OnTextChanged loses focus when AutoPostBack is true

2 Answers