Question

我打开一个具有写入权限的文件。但是，当我想再打开一个同名文件时，我得到一个例外。代码如下：

// Check to see if file was uploaded
            if (FileMdl.PostedFile != null)
            {
                // Get a reference to PostedFile object
                HttpPostedFile myFile = FileMdl.PostedFile;

                // Get size of uploaded file
                int nFileLen = myFile.ContentLength;

                // make sure the size of the file is > 0
                if (nFileLen > 0)
                {
                    // Allocate a buffer for reading of the file
                    byte[] myData = new byte[nFileLen];

                    // Read uploaded file from the Stream
                    myFile.InputStream.Read(myData, 0, nFileLen);

                    // Create a name for the file to store
                    Constantes.strFilenameMdl = Path.GetFileName(myFile.FileName);

                    // Write data into a file
                    WriteToFile(Server.MapPath("Files//" + Constantes.strFilenameMdl), ref myData);
                    myFile.InputStream.Flush();
                    myFile.InputStream.Close();


                }
            }


    private void WriteToFile(string strPath, ref byte[] Buffer)
    {
        // Create a file
        FileStream newFile = new FileStream(strPath, FileMode.Create,FileAccess.ReadWrite,FileShare.ReadWrite);

        // Write data to the file
        newFile.Write(Buffer, 0, Buffer.Length);

        // Close file
        newFile.Flush();
        newFile.Close();
        newFile.Dispose();
    }

据说Flush或Close或Dispose应该可以工作，但不是这样。有什么想法吗？

Answer 1

在写入文件之前，您曾尝试关闭上一个Stream：

                myFile.InputStream.Flush();
                myFile.InputStream.Close();

              // Write data into a file
                WriteToFile(Server.MapPath("Files//" + Constantes.strFilenameMdl), ref myData);

Answer 2

尝试像这样使用using语句：

    private void WriteToFile(string strPath, ref byte[] Buffer)
    {
        // Create a file
        using (FileStream newFile = new FileStream(strPath, FileMode.Create, FileAccess.ReadWrite, FileShare.ReadWrite))
        {
            // Write data to the file
            newFile.Write(Buffer, 0, Buffer.Length);
        }
    }

详情请见：http://msdn.microsoft.com/en-us/library/vstudio/yh598w02(v=vs.100).aspx

注意：您还可以通过从ref语句中删除输入参数和FileShare.ReadWrite参数中的FileStream键来简化代码，如下所示：

    private void WriteToFile(string strPath, byte[] Buffer)
    {
        // Create a file
        using (FileStream newFile = new FileStream(strPath, FileMode.Create, FileAccess.ReadWrite))
        {
            // Write data to the file
            newFile.Write(Buffer, 0, Buffer.Length);
        }
    }

例外：进程无法访问该文件，因为它正由另一个进程使用

2 个答案: