How to get javascript values in page load

<input type="hidden" id="hdnMiddlediv" runat="server" /> <script type="text/javascript"> document.getElementById('<%=hdnMiddlediv.ClientID %>').value='test'; </script> 

While page load i want access this value

See this thread,
Fetch JS return value in server side page_load event in asp.net[^]

Dines87 :

<input type="hidden" id="hdnMiddlediv" runat="server" /> <script type="text/javascript"> document.getElementById('<%=hdnMiddlediv.ClientID %>').value='test'; </script>
While page load i want access this value

It is clear that you will not see the value of this hidden field at first occurrence of page OnLoad because the order of execution is something like this :

page OnLoage (server) --- send output to client --->  client scripts run(hidden field is set here because it is a client side script) ---> page post back ---> page OnLoad (server)

To determine its a first OnLoad or it is not , use IsPostBack boolean variable in OnLoad event handler.

Hope it helps.

Hello,
Please try this code ..

<input type="hidden" id="hdnMiddlediv" runat="server" />

<script type="text/javascript">
        window.onload = function () {
            document.getElementById('<%=hdnMiddlediv.ClientID %>').value = 'test';
        };

        $(document).ready(function () {
            if (document.getElementById('<%=hdnMiddlediv.ClientID %>').value = '')
            { document.getElementById('<%=hdnMiddlediv.ClientID %>').value = 'test'; }
        });
    </script></script>