/// <summary>
 /// 构造函数
 /// </summary>
 /// <param name="entity">实体</param>
 public LuceneIndexChange(ILuceneIndexable entity)
 {
     Entity = entity;
     State  = LuceneIndexState.NotSet;
 }
 /// <summary>
 /// 构造函数
 /// </summary>
 /// <param name="entity">实体</param>
 /// <param name="state">变更状态</param>
 public LuceneIndexChange(ILuceneIndexable entity, LuceneIndexState state)
 {
     Entity = entity;
     State  = state;
 }
 /// <summary>
 /// 实体是否有某种状态
 /// </summary>
 /// <param name="state">状态</param>
 /// <returns></returns>
 private bool EntriesHaveState(LuceneIndexState state)
 {
     return(Entries.Any(x => x.State == state));
 }