System.IO.Compression.ZipStorer.ReadCentralDir C# (CSharp) Méthode

        public List<ZipFileEntry> ReadCentralDir()
        {
            if (this.CentralDirImage == null)
                throw new InvalidOperationException("Central directory currently does not exist");

            List<ZipFileEntry> result = new List<ZipFileEntry>();

            for (int pointer = 0; pointer < this.CentralDirImage.Length; )
            {
                uint signature = BitConverter.ToUInt32(CentralDirImage, pointer);
                if (signature != 0x02014b50)
                    break;

                bool encodeUTF8 = (BitConverter.ToUInt16(CentralDirImage, pointer + 8) & 0x0800) != 0;
                ushort method = BitConverter.ToUInt16(CentralDirImage, pointer + 10);
                uint modifyTime = BitConverter.ToUInt32(CentralDirImage, pointer + 12);
                uint crc32 = BitConverter.ToUInt32(CentralDirImage, pointer + 16);
                uint comprSize = BitConverter.ToUInt32(CentralDirImage, pointer + 20);
                uint fileSize = BitConverter.ToUInt32(CentralDirImage, pointer + 24);
                ushort filenameSize = BitConverter.ToUInt16(CentralDirImage, pointer + 28);
                ushort extraSize = BitConverter.ToUInt16(CentralDirImage, pointer + 30);
                ushort commentSize = BitConverter.ToUInt16(CentralDirImage, pointer + 32);
                uint headerOffset = BitConverter.ToUInt32(CentralDirImage, pointer + 42);
                uint headerSize = (uint)( 46 + filenameSize + extraSize + commentSize);

                Encoding encoder = encodeUTF8 ? Encoding.UTF8 : DefaultEncoding;

                ZipFileEntry zfe = new ZipFileEntry();
                zfe.Method = (Compression)method;
                zfe.FilenameInZip = encoder.GetString(CentralDirImage, pointer + 46, filenameSize);
                zfe.FileOffset = GetFileOffset(headerOffset);
                zfe.FileSize = fileSize;
                zfe.CompressedSize = comprSize;
                zfe.HeaderOffset = headerOffset;
                zfe.HeaderSize = headerSize;
                zfe.Crc32 = crc32;
                zfe.ModifyTime = DosTimeToDateTime(modifyTime);
                if (commentSize > 0)
                    zfe.Comment = encoder.GetString(CentralDirImage, pointer + 46 + filenameSize + extraSize, commentSize);

                result.Add(zfe);
                pointer += (46 + filenameSize + extraSize + commentSize);
            }

            return result;
        }

        /// <summary>
        ///     Removes one of many files in storage. It creates a new Zip file.
        /// </summary>
        /// <param name="zip">Reference to the current Zip object</param>
        /// <param name="zfes">List of Entries to remove from storage</param>
        /// <returns>True if success, false if not</returns>
        /// <remarks>This method only works for storage of type FileStream</remarks>
        public static bool RemoveEntries(ref ZipStorer zip, List <ZipFileEntry> zfes)
        {
            if (!(zip.zipFileStream is FileStream))
            {
                throw new InvalidOperationException("RemoveEntries is allowed just over streams of type FileStream");
            }


            //Get full list of entries
            List <ZipFileEntry> fullList = zip.ReadCentralDir();

            //In order to delete we need to create a copy of the zip file excluding the selected items
            string tempZipName   = Path.GetTempFileName();
            string tempEntryName = Path.GetTempFileName();

            try
            {
                ZipStorer tempZip = Create(tempZipName, string.Empty);

                foreach (ZipFileEntry zfe in fullList)
                {
                    if (!zfes.Contains(zfe))
                    {
                        if (zip.ExtractFile(zfe, tempEntryName))
                        {
                            tempZip.AddFile(zfe.Method, tempEntryName, zfe.FilenameInZip, zfe.Comment);
                        }
                    }
                }
                zip.Close();
                tempZip.Close();

                if (File.Exists(zip.fileName))
                {
                    File.Replace(tempZipName, zip.fileName, null, true);
                }
                else
                {
                    File.Move(tempZipName, zip.fileName);
                }

                zip = Open(zip.fileName, zip.access);
            }
            catch
            {
                return(false);
            }
            finally
            {
                if (File.Exists(tempZipName))
                {
                    File.Delete(tempZipName);
                }
                if (File.Exists(tempEntryName))
                {
                    File.Delete(tempEntryName);
                }
            }
            return(true);
        }