/// <summary>
/// Creates a file on the file system with the entry?s contents and the specified name.
/// The last write time of the file is set to the entry?s last write time.
/// This method does allows overwriting of an existing file with the same name.
/// </summary>
///
/// <exception cref="UnauthorizedAccessException">The caller does not have the required permission.</exception>
/// <exception cref="ArgumentException">destinationFileName is a zero-length string, contains only whitespace,
/// or contains one or more invalid characters as defined by InvalidPathChars. -or- destinationFileName specifies a directory.</exception>
/// <exception cref="ArgumentNullException">destinationFileName is null.</exception>
/// <exception cref="PathTooLongException">The specified path, file name, or both exceed the system-defined maximum length.
/// For example, on Windows-based platforms, paths must be less than 248 characters, and file names must be less than 260 characters.</exception>
/// <exception cref="DirectoryNotFoundException">The path specified in destinationFileName is invalid
/// (for example, it is on an unmapped drive).</exception>
/// <exception cref="IOException">destinationFileName exists and overwrite is false.
/// -or- An I/O error has occurred.
/// -or- The entry is currently open for writing.
/// -or- The entry has been deleted from the archive.</exception>
/// <exception cref="NotSupportedException">destinationFileName is in an invalid format
/// -or- The ZipArchive that this entry belongs to was opened in a write-only mode.</exception>
/// <exception cref="InvalidDataException">The entry is missing from the archive or is corrupt and cannot be read
/// -or- The entry has been compressed using a compression method that is not supported.</exception>
/// <exception cref="ObjectDisposedException">The ZipArchive that this entry belongs to has been disposed.</exception>
/// <param name="destinationFileName">The name of the file that will hold the contents of the entry.
/// The path is permitted to specify relative or absolute path information.
/// Relative path information is interpreted as relative to the current working directory.</param>
/// <param name="overwrite">True to indicate overwrite.</param>
public static void ExtractToFile(this ZipArchiveEntry source, string destinationFileName, bool overwrite)
{
if (source == null)
throw new ArgumentNullException(nameof(source));
if (destinationFileName == null)
throw new ArgumentNullException(nameof(destinationFileName));
// Rely on FileStream's ctor for further checking destinationFileName parameter
FileMode fMode = overwrite ? FileMode.Create : FileMode.CreateNew;
using (Stream fs = new FileStream(destinationFileName, fMode, FileAccess.Write, FileShare.None, bufferSize: 0x1000, useAsync: false))
{
using (Stream es = source.OpenWrite())
es.CopyTo(fs);
}
File.SetLastWriteTime(destinationFileName, source.LastWriteTime.DateTime);
}
internal static ZipArchiveEntry DoCreateEntryFromFile(ZipArchive destination,
string sourceFileName, string entryName, CompressionLevel? compressionLevel)
{
if (destination == null)
throw new ArgumentNullException(nameof(destination));
if (sourceFileName == null)
throw new ArgumentNullException(nameof(sourceFileName));
if (entryName == null)
throw new ArgumentNullException(nameof(entryName));
// Checking of compressionLevel is passed down to DeflateStream and the IDeflater implementation
// as it is a pluggable component that completely encapsulates the meaning of compressionLevel.
// Argument checking gets passed down to FileStream's ctor and CreateEntry
using (Stream fs = new FileStream(sourceFileName, FileMode.Open, FileAccess.Read, FileShare.Read, bufferSize: 0x1000, useAsync: false))
{
ZipArchiveEntry entry = compressionLevel.HasValue
? destination.CreateEntry(entryName, compressionLevel.Value)
: destination.CreateEntry(entryName);
DateTime lastWrite = File.GetLastWriteTime(sourceFileName);
// If file to be archived has an invalid last modified time, use the first datetime representable in the Zip timestamp format
// (midnight on January 1, 1980):
if (lastWrite.Year < 1980 || lastWrite.Year > 2107)
lastWrite = new DateTime(1980, 1, 1, 0, 0, 0);
entry.LastWriteTime = lastWrite;
using (Stream es = entry.OpenWrite())
fs.CopyTo(es);
return entry;
}
}
