private void ShowGrade()
{
Person myPerson = new Person();
DGrade grade=new DGrade();
DataTable dt = grade.GeGradeFullNameListBySchoolID(myPerson.School_id);
ddlGrade.DataTextField = "gradeName";
ddlGrade.DataValueField = "id";
ddlGrade.DataSource = dt;
ddlGrade.DataBind();
}
