C# Win App Linq ถ้าในกรณีนี้ผมไม่ต้องการเรียกฟังค์ชัน 2 รอบ ควรแก้โค้ดเป็นยังไง ครับ

int numberOfrecords=10;
listOfItems.OrderByDescending(x => x.CreatedDate).Take(numberOfrecords)

int total_min = GetDuration(file).TotalMinutes; // รอบเดียว

// linq

...total_min>11 || total_min< 2

(from file in Directory.GetFiles(@"D:\songTOR", "*.mp4")
             where GetDuration(file).TotalMinutes > 11 ||  GetDuration(file).TotalMinutes< 2
             select file).ToList<string>()
                .ForEach(f => {
                      try
                        {
                        File.Delete(f);

                        } catch { } });
                     
                  MessageBox.Show("complete");

 (from file in Directory.GetFiles(@"D:\songTOR", "*.mp4")
             where CheckDuration(file) //||File.Exists(file.Replace(".mp4", ".mp3")) // 
             select file).ToList<string>()
                .ForEach(f => {
                      try
                        {
                        File.Delete(f);

                        } catch { } });
                     
                  MessageBox.Show("complete");

 bool CheckDuration(string filePath)
        {
            double _TotalMinutes = GetDuration(filePath).TotalMinutes;
            return (_TotalMinutes > 11 || _TotalMinutes < 2);


        }

        //https://markheath.net/post/how-to-get-media-file-duration-in-c
        TimeSpan GetDuration(string filePath)
        {
            try
            {
                using (var shell = ShellObject.FromParsingName(filePath))
                {
                    IShellProperty prop = shell.Properties.System.Media.Duration;
                    var t = (ulong)prop.ValueAsObject;
                    return TimeSpan.FromTicks((long)t);
                }
            }
            catch { return TimeSpan.FromTicks((long)0) ; }

        }

var list = (from x in docs
            let temp = _storageService.GetFileUrl(x.FileName) // ประกาศตัวแปรใน from...in...
            select new NoneRequiredUserDocument
            {
                StudentDocument = x,
                Src = temp,
                ThumbnailImageUrl = ImageHelper.ThumbnailImageUrl(temp, 75)
            }).ToList();