C＃FileStream StreamWriter另一個進程異常

Question

我正在從DataGridView編寫CSV文件。 在此過程中（任務正在寫入文件時）打開文件時，出現錯誤，因為：

The process cannot access the file 'xyz\\filename.csv' because it is being used by another process.

我嘗試在每次寫入后在file和swOut上手動調用Flush()方法，但仍然收到錯誤。

我需要使用FileMode.Append因為在創建文件后，我添加了n行。 我已經嘗試了FileShare枚舉的每個不同選項，但是沒有任何效果。

我哪里錯了？

我的代碼：

using (FileStream file = new FileStream(output_file, FileMode.Append, FileAccess.Write, FileShare.Read))
{
    StreamWriter swOut = new StreamWriter(file);
    swOut.AutoFlush = true;
    if (table.Rows.Count == 2)
    {
        for (int i = 0; i <= table.Columns.Count - 1; i++)
        {
            if (i > 0)
            {
                swOut.Write(",");
            }
            swOut.Write(table.Columns[i].HeaderText);
        }
        swOut.WriteLine();
    }
    swOut.Write(category.Replace(",", " ") + "," + name.Replace(",", " ") + "," + address.Replace(",", " ") + "," + locality.Replace(",", " ") + "," + cap.Replace(",", " ") + "," + tel.Replace(",", " ") + "," + fax.Replace(",", " ") + "," + www.Replace(",", " ") + "," + email_results.Replace(",", " ") + "," + business_url.Replace(",", " ") + "," + map_query.Replace(",", " "));
    swOut.WriteLine();
    file.Close();
    if (stop == true) output_file = "";
}

Answer 1

為什么file.Close(); ？

它應該是swOut.Close();

編輯：

或者像這樣

'using (FileStream file = new FileStream(output_file, FileMode.Append, FileAccess.Write, FileShare.Read))
using (StreamWriter swOut = new File.AppendText(output_file))
{
    'StreamWriter swOut = new StreamWriter(file);
    swOut.AutoFlush = true;
    if (table.Rows.Count == 2)
    {
        for (int i = 0; i <= table.Columns.Count - 1; i++)
        {
            if (i > 0)
            {
                swOut.Write(",");
            }
            swOut.Write(table.Columns[i].HeaderText);
        }
        swOut.WriteLine();
    }
    swOut.Write(category.Replace(",", " ") + "," + name.Replace(",", " ") + "," + address.Replace(",", " ") + "," + locality.Replace(",", " ") + "," + cap.Replace(",", " ") + "," + tel.Replace(",", " ") + "," + fax.Replace(",", " ") + "," + www.Replace(",", " ") + "," + email_results.Replace(",", " ") + "," + business_url.Replace(",", " ") + "," + map_query.Replace(",", " "));
    swOut.WriteLine();
    swOut.Close();
    if (stop == true) output_file = "";
}

Answer 2

確保使用以下代碼關閉使用代碼中文檔的所有文件流

      Close();

范例：

    //Create the File
    FileStream FS = new FileStream("C:/Path to document",FileMode.Append,FileAccess.Write);
    //Call the Close Method to Close the file
    FS.Close();

確保所有文件流均已關閉，並且不會再出現此錯誤

Answer 3

好的，這是解決方案。

在我宣布之前

public FileStream file;

在主要班級。

然后，當它開始向datagridview添加行時，我初始化文件流：

file = new FileStream(output_file, FileMode.Append, FileAccess.Write, FileShare.Read);

然后每次我添加一行時，我也使用以下代碼在csv中添加一行：

 StreamWriter swOut =  new StreamWriter(file);
                        swOut.AutoFlush = true;
                        if (table.Rows.Count == 2)
                        {
                            for (int i = 0; i <= table.Columns.Count - 1; i++)
                            {
                                if (i > 0)
                                {
                                    swOut.Write(",");
                                }
                                swOut.Write(table.Columns[i].HeaderText);
                            }
                            swOut.WriteLine();
                        }
                        swOut.Write(category.Replace(",", " ") + "," + name.Replace(",", " ") + "," + address.Replace(",", " ") + "," + locality.Replace(",", " ") + "," + cap.Replace(",", " ") + "," + tel.Replace(",", " ") + "," + fax.Replace(",", " ") + "," + www.Replace(",", " ") + "," + email_results.Replace(",", " ") + "," + business_url.Replace(",", " ") + "," + map_query.Replace(",", " "));
                        swOut.WriteLine();
                        swOut.Close();
                        file.Close();
                        file = new FileStream(output_file, FileMode.Append, FileAccess.Write, FileShare.Read);
                        //file.Lock(0, file.Length);

因此，FileStream始終處於打開狀態，並且不會像我的原始代碼一樣每次都關閉。

謝謝！