c# - 无法使用 DeleteAsync 删除文件

Question

我在 VS2012、WinRT 和 C# 中工作。

我试图在解压后删除一些文件。我收到“访问被拒绝”错误。如果我停止该应用程序并重新启动它，相同的代码可以正常工作，所以看起来仍然有一个 handle 。

如果我不调用 unZipFile 方法，我可以删除文件。

是否有明确的方式来发布文件？在调用 delete 之前，我已将其设置为 null (file = null;)。

这是调用解压缩方法的代码块:

    StorageFile file = await CreateOutputFile(fileName, path);

        MemoryStream theMemStream = new MemoryStream();

        theMemStream.Write(bytes, 0, bytes.Length);

        await FileIO.WriteBytesAsync(file, bytes);

        await theMemStream.FlushAsync();
        theMemStream.Dispose();

        var result = await unZipFile(file, path);

        file = null;

这是 unZipFile 方法:

        private async Task<string> unZipFile(StorageFile file, string path)
        {

        StorageFolder sf = await GetOutputFolder(path);

    using (var zipStream = await file.OpenStreamForReadAsync())
    {
        using (MemoryStream zipMemoryStream = new MemoryStream((int)zipStream.Length))
        {

            await zipStream.CopyToAsync(zipMemoryStream);

            try
            {
                var archive = SharpCompress.Archive.ArchiveFactory.Open(file.Path);

                foreach (var entry in archive.Entries)
                {
                    entry.WriteTo(zipMemoryStream);

                    Stream fileData = entry.OpenEntryStream();

                    StorageFile outputFile = await sf.CreateFileAsync(entry.FilePath, CreationCollisionOption.ReplaceExisting);

                    using (Stream outputFileStream = await outputFile.OpenStreamForWriteAsync())
                    {
                        await fileData.CopyToAsync(outputFileStream);
                        await outputFileStream.FlushAsync();
                        outputFileStream.Dispose();
                    }
                }
                archive = null;
            }
            catch (Exception ex)
            {
                throw new IOException("Error writing decompressed output file: " + ex.Message);
            }

            await zipStream.FlushAsync();
            zipStream.Dispose();

            await zipMemoryStream.FlushAsync();
            zipMemoryStream.Dispose();
        }
    }

    return "success";
}

这是删除方法。解压后为每个文件调用:

private async Task<string> deleteFile(string path, string filename)
{
    StorageFolder folder = await GetOutputFolder(path);

    var files = await folder.GetFilesAsync();

    foreach (StorageFile file in files)
    {
        try
        {
            if (file != null)
            {
                if (file.Name == filename)
                    await file.DeleteAsync();
            }
        }
        catch (Exception ex)
        {
            return ex.Message;
        }
    }
    return "success";
}

Answer 1

在什么文件上出现异常，是提取的文件还是 zip 存档本身？

如果是后者，ArchiveFactory.Open() 返回一个继承IDisposable 的IArchive，所以你应该包装 var archive = SharpCompress.Archive.ArchiveFactory.Open(file.Path); 在 using block 中，以便在使用后处理。