/// <summary>
/// 比较
/// </summary>
/// <param name="oriD"></param>
/// <param name="newD"></param>
/// <returns></returns>
public ItemData Diff(ItemData oriD, ItemData newD)
{
headChanged = (oriD == null || LayoutItem.ValDiff <string>(oriD.head, newD.head));
return(newD);
}