Question

我在C＃中遇到了这个代码被执行的问题没有通过，它给我一个错误“文件被另一个进程使用”（或类似）。我已经尝试在Stack上寻找答案，但我无法将所有内容整合在一起。我试图在那里插入一些代码（就像他们说的那样），但只是给我更多的错误。请提前帮助，非常感谢！

以下是我当前的代码=＆gt;

// let's create example.py
string path = @"C:\example.py";
var stream = new FileStream(path, FileAccess.Read);
var reader = new StreamReader(stream);
if (!File.Exists(path)) {
    File.Create(path);
    TextWriter tw = new StreamWriter(path, true);
    tw.WriteLine("# code to insert into target file");
} else if (File.Exists(path)) {
    System.IO.File.WriteAllText(@"C:\example.py", string.Empty); // clear contents
    TextWriter tw = new StreamWriter(path, true);
    tw.WriteLine("# more code to insert into example.py");
}

这是我的原始代码（没有修复尝试）=＆gt;

// let's create example.py
string path = @"C:\example.py";
if (!File.Exists(path)) {
    File.Create(path);
    TextWriter tw = new StreamWriter(path, true);
    tw.WriteLine("# code to insert into target file");
} else if (File.Exists(path)) {
    System.IO.File.WriteAllText(@"C:\example.py", string.Empty); // clear contents
    TextWriter tw = new StreamWriter(path, true);
    tw.WriteLine("# more code to insert into example.py");
}

Answer 1

我发现这完全有效 - ＆gt;

// let's create example.py
const string path = @"C:\example.py";
using (FileStream fileStream = File.Open(path, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))
using (TextWriter sw = new StreamWriter(fileStream))
{
    {
        sw.WriteLine("First line");
        sw.WriteLine("Second line");
        sw.Close();
    }
}

Answer 2

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

只需删除File.Create并直接使用：

using (StreamWriter sw = new StreamWriter(path, true))
{
    // ...
}

Answer 3

您必须关闭FileStream返回的File.Create：

  File.Create(path).Close();

有关详细信息，请参阅MDSN

https://msdn.microsoft.com/en-us/library/d62kzs03(v=vs.110).aspx

然而，更好的方法是写入文件：

  if (File.Exists(path))
    File.AppendAllText(path, "# more code to insert into example.py");
  else 
    File.AppendAllText(path, "# code to insert into target file");

甚至

File.AppendAllText(path, File.Exists(path) 
  ? "# more code to insert into example.py"
  : "# code to insert into target file");

文件正由另一个进程使用

3 个答案: