使用 File.AppendAllText() 后文件被另一个进程使用

Question

进程无法访问文件 'file path'，因为它正被另一个进程使用。

我找到了这 2 个问题

File being used by another process after using File.Create()

和

Does File.AppendAllText close the file after the operation

这是一个 API，我有并且需要保存每一个进来的请求和出去的结果，可能有不止一个要求给定时间我的代码

public static void SaveTheRequestAndResponse(string type, SearchRequest searchRequest = null, dynamic result = null)
{
    var FilePath = AppDomain.CurrentDomain.BaseDirectory + @"SearchRequest";
    bool exists = Directory.Exists(FilePath);
    if (!exists)
    {
      var stream =  Directory.CreateDirectory(FilePath);
    }
    if (type == "request")
    {

        string Space = ", ";
        StringBuilder request = new StringBuilder();

        request.Append("Search Id : " + searchRequest.ID);
        request.Append(Space + "Company Name : " + searchRequest.CompanyName);
        request.Append(Space + "Country Code : " + searchRequest.CountryCode);

        request.Append(Space + "Search Type : " + searchRequest.SeacrhType);

        request.Append(Space + "Request Time : " + DateTime.Now + Environment.NewLine);

        var DataToBeSave = request.ToString();

        System.IO.File.AppendAllText(FilePath + @"\" + "FileNAme" + DateTime.Now.ToString("dd-MM-yyyy") + ".txt", DataToBeSave + Environment.NewLine);

    }
    else
    {
        string Space = ", ";
        StringBuilder SearchResult = new StringBuilder();
        SearchResult.Append("The result for Request" + Space);
        SearchResult.Append("Search Id : " + searchRequest.ID + Space);
        SearchResult.Append("States Code : " + result.StatusCode + Space);
        SearchResult.Append("Result Time : " + DateTime.Now + Environment.NewLine);

        var DataToBeSave = SearchResult.ToString();
        System.IO.File.AppendAllText(FilePath + @"\" + "FileNAme" + DateTime.Now.ToString("dd-MM-yyyy") + ".txt", DataToBeSave + Environment.NewLine);

    }
}

我的理解是 File.AppendAllText 将在操作后关闭，所以为什么我会收到此错误

Answer 1

我的代码存在竞争条件，这是因为 API 在每个给定时间被多个用户调用，即使

System.IO.File.AppendAllText(FilePath + @"\" + "FileNAme" + DateTime.Now.ToString("dd-MM-yyyy") + ".txt", DataToBeSave + Environment.NewLine);

将在操作后关闭，它仍然需要时间来完成它的工作，并且每次给定时间只能打开一个连接，因此需要锁定线程，这可以通过

完成

private static Object thisLock = new Object();
lock (thisLock)
{
    System.IO.File.AppendAllText(FilePath + @"\" + "DandB" + DateTime.Now.ToString("dd-MM-yyyy") + ".txt", DataToBeSave + Environment.NewLine);
}

感谢Abydal

使用 File.AppendAllText() 后文件被另一个进程使用

File being used by another process after using File.AppendAllText()

c#

file

system

saving-data