Represents a single entry in a ZipFile. Typically, applications get a ZipEntry by enumerating the entries within a ZipFile.
示例#1
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 internal ZipDirEntry(ZipEntry ze)
 {
 }
示例#2
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        internal static ZipEntry Create(String filename, string DirectoryPathInArchive)
        {
            ZipEntry entry = new ZipEntry();
            entry._LocalFileName = filename;
            if (DirectoryPathInArchive == null)
                entry._FileNameInArchive = filename;
            else
            {
                // explicitly specify a pathname for this file
                entry._FileNameInArchive =
                        System.IO.Path.Combine(DirectoryPathInArchive, System.IO.Path.GetFileName(filename));
            }

            entry._LastModified = System.IO.File.GetLastWriteTime(filename);

            // adjust the time if the .NET BCL thinks it is in DST.
            // see the note elsewhere in this file for more info.
            if (entry._LastModified.IsDaylightSavingTime())
            {
                System.DateTime AdjustedTime = entry._LastModified - new System.TimeSpan(1, 0, 0);
                entry._LastModDateTime = ZForge.Zip.Shared.DateTimeToPacked(AdjustedTime);
            }
            else
                entry._LastModDateTime = ZForge.Zip.Shared.DateTimeToPacked(entry._LastModified);

            // we don't actually slurp in the file until the caller invokes Write on this entry.

            return entry;
        }
示例#3
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        private static bool ReadHeader(System.IO.Stream s, ZipEntry ze)
        {
            int signature = ZForge.Zip.Shared.ReadSignature(s);

            // Return false if this is not a local file header signature.
            if (ZipEntry.IsNotValidSig(signature))
            {
                s.Seek(-4, System.IO.SeekOrigin.Current); // unread the signature
                // Getting "not a ZipEntry signature" is not always wrong or an error.
                // This can happen when walking through a zipfile.  After the last compressed entry,
                // we expect to read a ZipDirEntry signature.  When we get this is how we
                // know we've reached the end of the compressed entries.
                if (ZipDirEntry.IsNotValidSig(signature))
                {
                    throw new Exception(String.Format("  ZipEntry::Read(): Bad signature ({0:X8}) at position  0x{1:X8}", signature, s.Position));
                }
                return false;
            }

            byte[] block = new byte[26];
            int n = s.Read(block, 0, block.Length);
            if (n != block.Length) return false;

            int i = 0;
            ze._VersionNeeded = (short)(block[i++] + block[i++] * 256);
            ze._BitField = (short)(block[i++] + block[i++] * 256);
            ze._CompressionMethod = (short)(block[i++] + block[i++] * 256);
            ze._LastModDateTime = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;

            // the PKZIP spec says that if bit 3 is set (0x0008), then the CRC, Compressed size, and uncompressed size
            // come directly after the file data.  The only way to find it is to scan the zip archive for the signature of
            // the Data Descriptor, and presume that that signature does not appear in the (compressed) data of the compressed file.

            if ((ze._BitField & 0x0008) != 0x0008)
            {
                ze._Crc32 = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
                ze._CompressedSize = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
                ze._UncompressedSize = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
            }
            else
            {
                // the CRC, compressed size, and uncompressed size are stored later in the stream.
                // here, we advance the pointer.
                i += 12;
            }

            Int16 filenameLength = (short)(block[i++] + block[i++] * 256);
            Int16 extraFieldLength = (short)(block[i++] + block[i++] * 256);

            block = new byte[filenameLength];
            n = s.Read(block, 0, block.Length);
            ze._FileNameInArchive = ZForge.Zip.Shared.StringFromBuffer(block, 0, block.Length);

            // when creating an entry by reading, the LocalFileName is the same as the FileNameInArchivre
            ze._LocalFileName = ze._FileNameInArchive;

            ze._Extra = new byte[extraFieldLength];
            n = s.Read(ze._Extra, 0, ze._Extra.Length);

            // transform the time data into something usable
            ze._LastModified = ZForge.Zip.Shared.PackedToDateTime(ze._LastModDateTime);

            // actually get the compressed size and CRC if necessary
            if ((ze._BitField & 0x0008) == 0x0008)
            {
                long posn = s.Position;
                long SizeOfDataRead = ZForge.Zip.Shared.FindSignature(s, ZipConstants.ZipEntryDataDescriptorSignature);
                if (SizeOfDataRead == -1) return false;

                // read 3x 4-byte fields (CRC, Compressed Size, Uncompressed Size)
                block = new byte[12];
                n = s.Read(block, 0, block.Length);
                if (n != 12) return false;
                i = 0;
                ze._Crc32 = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
                ze._CompressedSize = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
                ze._UncompressedSize = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;

                if (SizeOfDataRead != ze._CompressedSize)
                    throw new Exception("Data format error (bit 3 is set)");

                // seek back to previous position, to read file data
                s.Seek(posn, System.IO.SeekOrigin.Begin);
            }

            return true;
        }
示例#4
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        /// <summary>
        /// Reads one ZipEntry from the given stream.  
        /// </summary>
        /// <param name="s">the stream to read from.</param>
        /// <returns>the ZipEntry read from the stream.</returns>
        public static ZipEntry Read(System.IO.Stream s)
        {
            ZipEntry entry = new ZipEntry();

            if (!ReadHeader(s, entry)) return null;

            entry.__filedata = new byte[entry.CompressedSize];
            int n = s.Read(entry._FileData, 0, entry._FileData.Length);
            if (n != entry._FileData.Length)
            {
                throw new Exception("badly formatted zip file.");
            }
            // finally, seek past the (already read) Data descriptor if necessary
            if ((entry._BitField & 0x0008) == 0x0008)
            {
                s.Seek(16, System.IO.SeekOrigin.Current);
            }
            return entry;
        }