asp.net大页面载入时以进度条显示zt

 protected void Page_Load(object sender, EventArgs e)
    {
        Response.Write("<div id='mydiv' >"); 
        Response.Write("_");
        Response.Write("</div>"); 
        Response.Write("<script>mydiv.innerText = '';</script>"); 
        Response.Write("<script language=javascript>;"); 
        Response.Write("var dots = 0;var dotmax = 10;function ShowWait()");
        Response.Write("{var output; output = '正在装载页面';dots++;if(dots>=dotmax)dots=1;");
        Response.Write("for(var x = 0;x < dots;x++){output += '·';}mydiv.innerText =  output;}");
        Response.Write("function StartShowWait(){mydiv.style.visibility = 'visible'; "); 
        Response.Write("window.setInterval('ShowWait()',1000);}"); 
        Response.Write("function HideWait(){mydiv.style.visibility = 'hidden';"); 
        Response.Write("window.clearInterval();}"); 
        Response.Write("StartShowWait();</script>");
        Response.Flush();
        Thread.Sleep(4000);//

    }