How to call a Javascript function having return value in c# codebehind

Question

I am having a page where i need to confirm whether to show updated grid or not

I am calling a javascript function using

ScriptManager.RegisterStartupScript(this, typeof(string), "Error", "confirm('Are u sure');", true);

What I want to know is how to get the return value of confirm in C# code behind.

Answer 1

Instead of this

ScriptManager.RegisterStartupScript(this, typeof(string), "Error", "confirm('Are u sure');", true);

use this

ScriptManager.RegisterStartupScript(this, typeof(string), "Error", "ConfirmUser('Are u sure');", true);

<script type='javascript'>
 function ConfirmUser(msg)
 {
  if(confirm(msg))
    __doPostBack('','');
 }
<script>

see following links to know more about __doPostBack

1 2

Answer 2

I am having a page where i need to confirm whether to show updated grid or not

You may prevent the postback when use choose Cancel button of confirm dialog.

<asp:Button ID="Button1" runat="server" 
            OnClientClick="return confirm('Are you sure to populate the list?');" 
            Text="Button" onclick="Button1_Click" />