How to call javascript on user control

[Zagete]

I have webapplication in c# asp.net 4.0 I have User Control in that I have written javascript :-\[code\]<script> function SetValue() { alert(document.getElementById('offSetClient').value); }</script><asp:HiddenField ID="clientDateTime" runat="server" /><asp:HiddenField ID="offSetClient" runat="server" Value="http://stackoverflow.com/questions/14081017/Test"/>\[/code\]and this User Control added into a web form.Please suggest me how can I call this javascript on User Control page load.