如何使用 SharpZipLib 将 ZipFile 写入磁盘 [关闭]

Question

如何使用 SharpZipLib 将ZipFile 写入磁盘？

• 是否必须打开输出流才能将ZipFile 写入磁盘？
• 有没有办法只获取ZipFile 字节并执行File.WriteAllBytes()？

注意：我的问题与压缩无关。只需将现有的ZipFile 写入磁盘即可。

另外，请注意，我已经阅读过文档，但没有这个用例。

https://github.com/icsharpcode/SharpZipLib/wiki/Zip-Samples

Answer 1

是否必须打开输出流才能将 ZipFile 写入磁盘？

根据他们的Github 示例，他们建议使用ZipOutputStream 创建一个流对象来写入文件并写入正在压缩的文件中，您需要打开一个FileStream 将对象写入图书馆。

这是可用于压缩文件的代码示例。

// Depending on the directory this could be very large and would require more attention
// in a commercial package.
string[] filenames = Directory.GetFiles("directory");

// 'using' statements guarantee the stream is closed properly which is a big source
// of problems otherwise.  Its exception safe as well which is great.
using (ZipOutputStream s = new ZipOutputStream(File.Create("outputfile")))
{

    s.SetLevel(9); // 0 - store only to 9 - means best compression

    byte[] buffer = new byte[4096];

    foreach (string file in filenames)
    {

        // Using GetFileName makes the result compatible with XP
        // as the resulting path is not absolute.
        var entry = new ZipEntry(Path.GetFileName(file));

        // Setup the entry data as required.

        // Crc and size are handled by the library for seakable streams
        // so no need to do them here.

        // Could also use the last write time or similar for the file.
        entry.DateTime = DateTime.Now;
        s.PutNextEntry(entry);

        using (FileStream fs = File.OpenRead(file)) 
        {

            // Using a fixed size buffer here makes no noticeable difference for output
            // but keeps a lid on memory usage.
            int sourceBytes;
            do
            {
            sourceBytes = fs.Read(buffer, 0, buffer.Length);
            s.Write(buffer, 0, sourceBytes);
            } while (sourceBytes > 0);
        }
    }

    // Finish/Close arent needed strictly as the using statement does this automatically

    // Finish is important to ensure trailing information for a Zip file is appended.  Without this
    // the created file would be invalid.
    s.Finish();

    // Close is important to wrap things up and unlock the file.
    s.Close();
}

有什么方法可以获取 ZipFile 字节并执行 File.WriteAllBytes()？

如果您问我们是否可以直接写入文件的字节而不打开FileStream 来读取要写入 zip 文件中的文件，那么，是的，您可以一次将所有字节写入源zip 文件，但这是一种不好的方法，因为它会一次将所有字节读入内存，如果被压缩的文件很大，这可能是灾难性的。无论如何，这是你可以做到的：

只需将上述示例中的FileStream 部分替换为以下代码即可：

var bytes = File.ReadAllBytes(file);
s.Write(bytes, 0, bytes.Length); // write all bytes from 0 to the length of the bytes

因此，更新后的源代码将是：

string[] filenames = Directory.GetFiles("directory");

using (ZipOutputStream s = new ZipOutputStream(File.Create("outputfile")))
{

    s.SetLevel(9);

    byte[] buffer = new byte[4096];

    foreach (string file in filenames)
    {
        var entry = new ZipEntry(Path.GetFileName(file));

        entry.DateTime = DateTime.Now;
        s.PutNextEntry(entry);
        var bytes = File.ReadAllBytes(file);
        s.Write(bytes, 0, bytes.Length);
    }
    s.Finish();
    s.Close();
}