Add class into html tag by JQuery in ASP.NET C#

Question

I tried to add class in tag

but when the web form postback it lost :(

<ul>
<li><asp:Linkbutton runat="server" Text="Text1"/></li>
<li class="active"><asp:Linkbutton runat="server" Text="Text2"/></li>

and this is my JQuery Code

<script>
    $(document).ready(function () {
        $("li").click(function () {
            $("li").removeClass();
            $(this).addClass("active");
        });
    });
</script>

Answer 1

Nothing that isn't runat="server" can be persisted; you need to store information about selected element (somewhere) - either utilize which link was clicked or store id of last clicked element into hidden field:

<ul>
    <li id="uid1"><asp:Linkbutton ID="Linkbutton1" runat="server" Text="Text1"/></li>
    <li id="uid2" class="active"><asp:Linkbutton ID="Linkbutton2" runat="server" Text="Text2"/></li>
</ul>

<asp:HiddenField ID="hfActive" runat="server" />

<script type="text/javascript">
    $(document).ready(function () {
        var sId = $('#<%= hfActive.ClientID %>').val();
        if (sId != "") {
            $("li").removeClass();
            $('#' + sId).addClass("active");
        }

        $("li").click(function () {
            $('#<%= hfActive.ClientID %>').val($(this).attr('id'));
            $("li").removeClass();
            $(this).addClass("active");
        });
    });
</script>

Note: the "li" elements have to have unique id assigned in this case.

Answer 2

<ul>
   <li id="lnkbtn1" runat="server"><a href="Default1.aspx"><span>Text1</span></a></li>
   <li id="lnkbtn2" runat="server"><a href="Default2.aspx"><span>Text2</span></a></li>
</ul>

In Code File

protected void Page_Load(object sender, EventArgs e)
{
    setCurrentPage();  
}

private void setCurrentPage()
{
    var pagename = Convert.ToString(GetPageName());
    switch (pagename)
    {
        case "Default1.aspx":
            lnkbtn1.Attributes["class"] = "active";
            break;
        case "Default2.aspx":
            lnkbtn2.Attributes["class"] = "active";
            break;            
    }
}

private object GetPageName()
{
    return Request.Url.ToString().Split('/').Last();
}