记录上级页面并返回(本页面刷新不作为上级页面)

刷新|页面

protected static string requestPageUrl = string.Empty;
private void Page_Load(object sender, System.EventArgs e)
{
    if(!this.IsPostBack)
    {
        requestPageUrl = Request.UrlReferrer.ToString();
    }
}
private void btn_Back_Click(object sender, System.EventArgs e)
{
    Response.Redirect(requestPageUrl);
}