how to access hidden field value even after page refresh

Hi All
I used a hidden field control in web user control. And am assigning a value to that txtValue(hidden field) using jquery through asp.net webservice and am reloading the same page after the jquery function. After reloading the page, I triedt to access the txtValue.Value.
But every time it is showing the txtValue.Value as empty. How to access the txtValue value, even though the page is reloaed.

<asp:HiddenField runat="server" ID="txtValue" Value="" />


Thanks in Advance,
Soori.

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