How to Update the UpdatePanel from Server Side in Asp.Net

Updating the panel form code behind is easy, you need to call the public method Update() in the code behind and rest will be taken care.

Deafult.aspx

<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
            <ContentTemplate>
            <h4>Inside UpdatePanel - 1</h4>
                <asp:Label ID="lblUpdatePanel1st" runat="server" EnableViewState="false" /> <br />
                <asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClick="RefreshTheTime" />
            </ContentTemplate>
        </asp:UpdatePanel>

Default.aspx.cs

protected void RefreshTheTime(object sender, EventArgs e)
    {
        lblUpdatePanel1st.Text = DateTime.Now.ToString();
     
        // try commenting following line and see that time will not be updated
        UpdatePanel2.Update();    }

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