1 static void Main(string[] args)  2         {
    3  4             FileInfo[] fileInfos = new DirectoryInfo(".\\").GetFiles("*.log", SearchOption.TopDirectoryOnly);  5             List
     
       fileInfoList = new List
      
       (fileInfos);  6             fileInfoList.Sort(  7                 new Comparison
       
        (  8                     delegate(FileInfo a, FileInfo b)  9                     {
   10                         return a.CreationTime.CompareTo(b.CreationTime); 11                     } 12                 ) 13             ); 14 15             for (int i = fileInfoList.Count; i > 5; i--) 16             {
   17                 File.Delete(fileInfoList[0].FullName); 18                 fileInfoList.RemoveAt(0); 19             } 20 21             foreach (FileInfo fi in fileInfoList) 22             {
   23                 Console.WriteLine(fi.Name + "--" + fi.CreationTime.ToLongTimeString()); 24             } 25 26             Console.Read(); 27         }
       
      
     

    类似地，可以通过修改排序依据，实现其他诸如保留最大（小）、最近修改等功能。