using System; using System.Linq; namespace ConsoleApplication1 {     /// <summary>     /// 给出一段英文，分类统计（如：长度为4的单词有2个：time，well）     /// </summary>     class Program     {         static void Main(string[] args)         {             string source = "Do one thing at a time,and do well";//已知英文语句             string[] stringArray = source.Split(new char[] { ' ', ',' });             var result = stringArray.GroupBy(s => s.Length).Select(s => new {                 Lenght = s.Select(x => x).FirstOrDefault().Length,                 Count = s.Count(),                 StringItems = s.Select(x => x)             });             foreach (var s in result)             {                 string strResult = string.Empty;                 foreach (var item in s.StringItems)                 {                     strResult += string.IsNullOrEmpty(strResult) ? item : " , " + item;                 }                 Console.WriteLine(string.Format("长度为{0}的单词有{1}个：{2}", s.Lenght, s.Count, strResult));             }                        Console.ReadKey();         }     } }