public void GetLoadedCenterDropDownList()
        {
            int id = Convert.ToInt16(thanaDropDownList.SelectedValue);

            centerDropDownList.DataSource     = centerManager.GetAllCentersByThana(id);
            centerDropDownList.DataValueField = "Id";
            centerDropDownList.DataTextField  = "Name";
            centerDropDownList.DataBind();
        }