頁面加載友好提示的問題

public partial class Default2 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack && Request.QueryString["AJax"] == null)
        {  
            Response.Write("<script language=\"JavaScript\">");
            Response.Write("    document.write(''加載中'');");         
            Response.Write("    var XMLhttp = false;");
            Response.Write("    var xmlhttp = new ActiveXObject(\"Microsoft.XMLHTTP\");");
            Response.Write("    XMLhttp.open(\"POST\",\"Default2.ASPx?AJax=1\",true);");
            Response.Write("    XMLhttp.send(null);");
            Response.Write("    XMLhttp.onreadystatechange=function()");
            Response.Write("    {");
            Response.Write("        if ( xmlhttp.readyState==4 || XMLhttp.readyState==''complete'')");
            Response.Write("        {");
            Response.Write("            document.write( XMLhttp.responseText);");
            Response.Write("           {");