how to calculate client browser window width

you can find in this tutorial

http://www.java-samples.com/showtutorial.php?tutorialid=1015[^]

if you want to get this in codebehind

if you want to use this clearly please dont forget add script jquery and ScriptManagerin page

in your html line put this in body

<input type="hidden" id="inptWidth"  runat="server" />
<input type="hidden" id="inptHeight" runat="server" />

your script

<script type="text/javascript">

    // this is a jquery syntax
    $(document).ready(function() {
        var inptWidth = $get('<%=inptWidth.ClientID %>');// you must to use in page ScriptManager
        var inptHeight = $get('<%=inptHeight.ClientID %>');
        inptWidth.value = window.innerWidth;
        inptHeight.value = window.innerHeight;
    });

</script>

and this my anybuttons click event

protected void btnControl_Click(object sender, EventArgs e)
        {           
            string val = inptWidth.Value;           
        }

dont forget you cant do this in load of page. because clientside loading occuring after server-side loading.