GroupBy

string[] Words = new string[] { "what", "is", "your", "name", "?", "my", "name", "is", "lyf","." };
var Groups = from word in Words
                    group word by word.Length into lengthGroups //按单词长度将单词分组
                    orderby lengthGroups.Key descending //按单词长度降序排列
                    select new
{
   Length = lengthGroups.Key, //取单词长度
   WordCollect = lengthGroups //取该长度的单词分组集合
};
foreach (var group in Groups) //遍历每组单词
{
   Response.Write("包含" + group.Length.ToString() + "个字符的单词有:" + "<br/>");
   foreach (string word in group.WordCollect)
   {
      Response.Write("&nbsp;&nbsp;&nbsp;&nbsp;" + word + "<br/>");
   }
}