partial void Deletepage(page instance);
 partial void Updatepage(page instance);
 private void detach_pages(page entity)
 {
     this.SendPropertyChanging();
     entity.pageCategory = null;
 }
 partial void Insertpage(page instance);
 private void attach_pages(page entity)
 {
     this.SendPropertyChanging();
     entity.pageCategory = this;
 }