C# CopyFileEX Copy Physical Sectors and Write to a Logical File

CopyFileEx.cs

public bool CopyFileEx(string sourceFile, string targetFile)
        {
            long bytesLeft      = 0;
            long bytesProcessed = 0;
            long sectorsCopied  = 0;
            var  fileinfo       = new FileInfo(sourceFile);
            var  fileFragments  = FileFragments.GetFileAllocation(sourceFile);
            if(fileFragments.TotalFragments == 0 || fileinfo.Length == 0)
                return false;
            var device = new Device(512);
            device.OpenDeviceForReading(sourceFile[0].ToString(), Device.ODDevType.Logical);
            using(var stream = new FileStream(targetFile, FileMode.Create, FileAccess.Write, FileShare.Write, 4096, true))
            {
                for(var i = 0; i < fileFragments.TotalFragments; i++)
                {
                    foreach(var e in fileFragments.FileAllocation)
                    {
                        var Sector = e.StartingSector;
                        do
                        {
                            var buf = device.ReadSector(Sector);
                            if(fileinfo.Length < 512)
                            {
                                stream.Write(buf, 0, (int) fileinfo.Length);
                                goto Tag1;
                            }
                            stream.Write(buf, 0, 512);
                            bytesProcessed += 512;
                            bytesLeft      =  fileinfo.Length - bytesProcessed;
                            if(bytesLeft != 0)
                                if(bytesLeft < 512)
                                {
                                    buf = device.ReadSector(Sector + 1);
                                    stream.Write(buf, 0, (int) bytesLeft);
                                    goto Tag1;
                                }
                            Sector++;
                            sectorsCopied++;
                            if(sectorsCopied > e.NumberOfSectors)
                            {
                                sectorsCopied = 0;
                                break;
                            }
                            if(bytesLeft <= 0)
                                break;
                        } while(bytesLeft > 0);
                    }
                    if(bytesLeft <= 0)
                        break;
                }
            }
            Tag1:
            device.CloseInDevice();
            return true;
        }