/// <summary>
 /// sen[offset]后tailLen长的词是否存在
 /// </summary>
 /// <param name="node"></param>
 /// <param name="sen"></param>
 /// <param name="offset"></param>
 /// <param name="tailLen"></param>
 /// <returns></returns>
 public int search(CharNode node, char[] sen, int offset, int tailLen)
 {
     if (node != null)
     {
         return(node.IndexOf(sen, offset, tailLen));
     }
     return(-1);
 }
 /// <summary>
 /// sen[offset]后tailLen长的词是否存在
 /// </summary>
 /// <param name="node"></param>
 /// <param name="sen"></param>
 /// <param name="offset"></param>
 /// <param name="tailLen"></param>
 /// <returns></returns>
 public int search(CharNode node, char[] sen, int offset, int tailLen)
 {
     if (node != null)
         return node.IndexOf(sen, offset, tailLen);
     return -1;
 }