jQuery and ASP.NET Page load-Collection of common programming errors

I test jQuery and ASP.NET with Webcontrols and in my test load the Side everytime new if I click on the Button. The jQuery Code add a Css Class to a Label.

My aspx:

      





    jQuery Anwendung

    

    
        .CssKlasse 
        {
            background:red;
            font-size:40px; 
            }
    

    

        $(document).ready(function () {
            $("#").click(function (event) {
                $("#").slideToggle('slow');
            });

        });

    



    
    
        
         
    
    

What can I do?

tarasov