ZipArchive创建无效的ZIP条目

时间:2017-02-20 16:24:17

标签: c# zip system.io.compression

我正在使用ZipArchive并且它主要工作,我看到的一个问题是当文件下载时我无法使用Windows默认存档例程打开它。如果我单击zip文件并提取所有内容,我会收到一条错误消息,指出没有要提取的条目。任何人都知道为什么会这样吗?为了它的价值,我可以用7zip打开同一个文件并提取文件就好了。

    public virtual ActionResult GetZip()
    {
        var summary = GetBytes();
        var response = new MemoryStream();
        using (var stream = new MemoryStream())
        {
            using (var archive = new ZipArchive(stream, ZipArchiveMode.Create, true))
            {
                var entry = archive.CreateEntry("myfiletozip" + fileExt);

                using (var writer = new BinaryWriter(entry.Open()))
                {
                    writer.Write(summary, 0, summary.Length);
                }
                stream.Seek(0, SeekOrigin.Begin);
                stream.CopyTo(response);
            }
        }

        response.Seek(0, SeekOrigin.Begin);

        return this.File(response, MediaTypeNames.Application.Zip, "myzipfilename.zip");
    }

更新:

找到这个SO Answer并修改了我的来源,它正在工作......我仍然不知道为什么。

        byte[] response;
        using (var stream = new MemoryStream())
        {
            using (var archive = new ZipArchive(stream, ZipArchiveMode.Create, true))
            {
                var entry = archive.CreateEntry("myfiletozip" + fileExt, CompressionLevel.Optimal);
                using (var entryStream = entry.Open())
                using (var fileToCompressStream = new MemoryStream(summary))
                {
                    fileToCompressStream.CopyTo(entryStream);
                }
            }
            response = stream.ToArray();
        }

1 个答案:

答案 0 :(得分:0)

ZipArchive在处理流时会向流中添加一些额外的信息(例如.checksum),因此在放置ZipArchive对象之前,不应该寻找流或使用它。

public virtual ActionResult GetZip()
{
    var summary = GetBytes();
    var response = new MemoryStream();
    using (var stream = new MemoryStream())
    {
        using (var archive = new ZipArchive(stream, ZipArchiveMode.Create, true))
        {
            var entry = archive.CreateEntry("myfiletozip" + fileExt);

            using (var writer = new BinaryWriter(entry.Open()))
            {
                writer.Write(summary, 0, summary.Length);
            }
        }
        //Use stream after archive is disposed
        stream.Seek(0, SeekOrigin.Begin);
        stream.CopyTo(response);
    }

    response.Seek(0, SeekOrigin.Begin);

    return this.File(response, MediaTypeNames.Application.Zip, "myzipfilename.zip");
}