我使用这个解决方案，但我有一个时间间隔，当我检查文件锁定与isfilellocked函数和当我打开文件。在这个时间跨度内，其他线程可以打开这个文件，所以我将得到IOException。

因此，我为此添加了额外的代码。在我的情况下，我想加载XDocument:

        XDocument xDoc = null;

        while (xDoc == null)
        {
            while (IsFileBeingUsed(_interactionXMLPath))
            {
                Logger.WriteMessage(Logger.LogPrioritet.Warning, "Deserialize can not open XML file. is being used by another process. wait...");
                Thread.Sleep(100);
            }
            try
            {
                xDoc = XDocument.Load(_interactionXMLPath);
            }
            catch
            {
                Logger.WriteMessage(Logger.LogPrioritet.Error, "Load working!!!!!");
            }
        }

你怎么看?我能改点东西吗?也许我没有使用IsFileBeingUsed函数在所有?

谢谢

我所知道的唯一方法是使用Win32独占锁API，这不是太快，但例子存在。

对于大多数人来说，一个简单的解决方案就是尝试/捕捉/睡眠循环。

更新了该解决方案的说明:使用FileAccess检查。对于只读文件，ReadWrite将失败，因此解决方案已修改为使用FileAccess.Read进行检查。

原: 在过去的几年里，我一直在使用这段代码，没有遇到过任何问题。

理解你在使用异常时的犹豫，但你不能总是避免它们:

protected virtual bool IsFileLocked(FileInfo file)
{
    try
    {
        using(FileStream stream = file.Open(FileMode.Open, FileAccess.Read, FileShare.None))
        {
            stream.Close();
        }
    }
    catch (IOException)
    {
        //the file is unavailable because it is:
        //still being written to
        //or being processed by another thread
        //or does not exist (has already been processed)
        return true;
    }

    //file is not locked
    return false;
}

这样的东西会有用吗?

var fileWasWrittenSuccessfully = false;
while (fileWasWrittenSuccessfully == false)
{
    try
    {
        lock (new Object())
        {
            using (StreamWriter streamWriter = new StreamWriter("filepath.txt"), true))
            {
                streamWriter.WriteLine("text");
            }
        }

        fileWasWrittenSuccessfully = true;
    }
    catch (Exception)
    {

    }
}

您可以返回一个任务，它会在流可用时立即提供给您。这是一个简化的解决方案，但却是一个很好的起点。是线程安全的。

private async Task<Stream> GetStreamAsync()
{
    try
    {
        return new FileStream("sample.mp3", FileMode.Open, FileAccess.Write);
    }
    catch (IOException)
    {
        await Task.Delay(TimeSpan.FromSeconds(1));
        return await GetStreamAsync();
    }
}

你可以像往常一样使用这个流:

using (var stream = await FileStreamGetter.GetStreamAsync())
{
    Console.WriteLine(stream.Length);
}

I once needed to upload PDFs to an online backup archive. But the backup would fail if the user had the file open in another program (such as PDF reader). In my haste, I attempted a few of the top answers in this thread but could not get them to work. What did work for me was trying to move the PDF file to its own directory. I found that this would fail if the file was open in another program, and if the move were successful there would be no restore-operation required as there would be if it were moved to a separate directory. I want to post my basic solution in case it may be useful for others' specific use cases.

string str_path_and_name = str_path + '\\' + str_filename;
FileInfo fInfo = new FileInfo(str_path_and_name);
bool open_elsewhere = false;
try
{
    fInfo.MoveTo(str_path_and_name);
}
catch (Exception ex)
{
    open_elsewhere = true;
}

if (open_elsewhere)
{
    //handle case
}