/// <summary>/// 删除某个时间之前的所有文件/// </summary>/// <param name="aUrl"></param>/// <param name="aTime"></param>public static void RemoveFile(string aUrl,DateTime aTime) {var bFiles = Directory.GetFiles(aUrl).Select(r => new { LastWriteTime = Directory.GetLastWriteTime(r),Path = r }).ToList() ;var bDelFiles = bFiles.Where(r => r.LastWriteTime <= aTime).ToList();foreach (var item in bDelFiles) {File.Delete(item.Path);}}