While taking interviews for asp.net candidate I am often asking this question but most peoples are not able to give this answer. So I decided to write a blog post about this. Here is the scenario. There are two
update panels in my html code in first
update panel there is textbox hello world and another
update panel there is a button called btnHelloWorld. Now I want to
update textbox text in button click event without post back. But in normal scenario It will not
update the textbox text as both are in different
update panel. Here is the code for that. <form id="form1" runat="server">
<asp:ScriptManager ID="myScriptManager" runat="server" EnableCdn="true"></asp:ScriptManager>
<asp:UpdatePanel ID="firstUpdatePanel" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="txtHelloWorld" runat="server"></asp:TextBox>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="secondUpdatePanel" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Button ID="btnHelloWorld" runat="server" Text="Print Hello World"
onclick="btnHelloWorld_Click" />
</ContentTemplate>
</asp:UpdatePanel>
</form>
Here comes magic!!. Lots of people don’t know that
update panel are providing the
Update method from which we can programmatically
update the
update panel elements without post back. Below is code for that.
protected void btnHelloWorld_Click(object sender, System.EventArgs e)
{
txtHelloWorld.Text = "Hello World!!!";
firstUpdatePanel.Update();
}
That’s it here I have updated the firstUpdatePanel from the code!!!. Hope you liked it.. Stay tuned for more..Happy Programming..
Technorati Tags: UpdatePanel,ASP.NET
