protected void Page_Load(object sender, EventArgs e) { if (Session["UserInfo"] != null) { user = Session["UserInfo"] as UserInfo; } courseid = Request.QueryString["CourseID"]; System.Text.RegularExpressions.Regex rex = new System.Text.RegularExpressions.Regex(@"^\d+$"); if (courseid == null || !rex.IsMatch(courseid)) { Response.Redirect("/aspx/CourseList.aspx"); } course.CourseID = int.Parse(courseid); course.UserID = user.UserID; course.GetCourseInfo(); Teacher_TA = course.GetCourseTeacher(); mycomment = course.GetMyCourseComment(); if (!Page.IsPostBack) { AllDataBind(); } }