根据Microsoft Docs ,如果要提取 zip 文件的目标目录已存在,程序应抛出 IOException。此外,“备注”部分指出“目标目录不能已存在”。然而,
ZipFile.ExtractToDirectory("archive.zip", ".\\output");
即使 output
作为目录存在,也能正常工作(没有异常(exception))。类似的东西
ZipFile.ExtractToDirectory("archive.zip", "\\");
也无异常(exception)地工作。因此,我试图理解为什么当 Microsoft 文档明确建议应该有异常(exception)时却没有异常(exception)。
注意:我正在运行 .NET 5。
最佳答案
看起来像是文档错误。我为此打开了两个 GitHub 问题,one for the source code comments和 one for the docs page由它们创建的
.NET Core 是开源的,这意味着我们可以检查实际的源代码以了解发生了什么。
ZipFile.ExtractToDirectory实际上调用 ZipFileExtensions.ExtractToDirectory(ZipArchive, String)方法:
public static void ExtractToDirectory(string sourceArchiveFileName, string destinationDirectoryName, Encoding? entryNameEncoding, bool overwriteFiles)
{
if (sourceArchiveFileName == null)
throw new ArgumentNullException(nameof(sourceArchiveFileName));
using (ZipArchive archive = Open(sourceArchiveFileName, ZipArchiveMode.Read, entryNameEncoding))
{
archive.ExtractToDirectory(destinationDirectoryName, overwriteFiles);
}
}
在 the actual code如果目标目录存在,则不会抛出 IOException,即使文档网站是这样说的:
/// <exception cref="IOException">An archive entry?s name is zero-length, contains only whitespace, or contains one or more invalid
/// characters as defined by InvalidPathChars. -or- Extracting an archive entry would have resulted in a destination
/// file that is outside destinationDirectoryName (for example, if the entry name contains parent directory accessors).
/// -or- An archive entry has the same name as an already extracted entry from the same archive.</exception>
public static void ExtractToDirectory(this ZipArchive source, string destinationDirectoryName, bool overwriteFiles)
{
if (source == null)
throw new ArgumentNullException(nameof(source));
if (destinationDirectoryName == null)
throw new ArgumentNullException(nameof(destinationDirectoryName));
foreach (ZipArchiveEntry entry in source.Entries)
{
entry.ExtractRelativeToDirectory(destinationDirectoryName, overwriteFiles);
}
}
看起来 learn.microsoft.com
位于实际源文档的后面。
为了完整起见,internal ExtractRelativeToDirectory method明确认为现有目标文件夹是有效的情况:
internal static void ExtractRelativeToDirectory(this ZipArchiveEntry source, string destinationDirectoryName, bool overwrite)
{
if (source == null)
throw new ArgumentNullException(nameof(source));
if (destinationDirectoryName == null)
throw new ArgumentNullException(nameof(destinationDirectoryName));
// Note that this will give us a good DirectoryInfo even if destinationDirectoryName exists:
DirectoryInfo di = Directory.CreateDirectory(destinationDirectoryName);
...
强调:
// Note that this will give us a good DirectoryInfo even if destinationDirectoryName exists
关于c# - 当目录存在时 ZipFile.ExtractToDirectory 是否抛出异常?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/67806595/