private void ShowStudentMessages()
 {
     DataLayer dl = new DataLayer();
     DataTable dt = dl.GetContactBookMessageByStudent((new Person()).people_id);
     gvList.DataSource = dt;
     gvList.DataBind();
 }
 private void ShowStudentMessages()
 {
     DataLayer dl = new DataLayer();
     DataTable dt = dl.GetContactBookMessageByStudent(Request["people_id"]);
     gvList.DataSource = dt;
     gvList.DataBind();
 }