protected void Page_Load(object sender, EventArgs e)
{
ShowLoading();
System.Threading.Thread.Sleep(10000);
ClientScript.RegisterClientScriptBlock(typeof(string), "", "");
}

///

/// 显示页面正在加载中效果
///

public void ShowLoading()
{
StringBuilder s = new StringBuilder();
s.Append(" \n");
s.Append("\n");
s.Append("\n ");
//HttpContext.Current.Response.Write(s.ToString());
HttpContext.Current.Response.Write(s.ToString());
//HttpContext.Current.Response.Flush();