在C#中安全地处理Excel互操作对象

我正在开发一个winforms c#visualstudio2008应用程序。该应用程序可以与excel文件进行对话，我正在使用Microsoft.Office.Interop.Excel;来实现这一点。

我想知道，即使出现错误，我如何确保对象被释放？

这是我的代码：

private void button1_Click(object sender, EventArgs e)
{
    string myBigFile="";
    OpenFileDialog openFileDialog1 = new OpenFileDialog();
    DialogResult result = openFileDialog1.ShowDialog(); // Show the dialog.
    if (result == DialogResult.OK) // Test result.
        myBigFile=openFileDialog1.FileName;
    Excel.Application xlApp;
    Excel.Workbook xlWorkBook;
    Excel.Worksheet xlWorkSheet;
    Excel.Range range;
    string str;
    int rCnt = 0;
    int cCnt = 0;
    xlApp = new Excel.ApplicationClass();
    xlWorkBook = xlApp.Workbooks.Open(myBigFile, 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "'t", true, false, 0, true, 1, 0);
    xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);
    range = xlWorkSheet.UsedRange;
    /*
    for (rCnt = 1; rCnt <= range.Rows.Count; rCnt++)
    {
        for (cCnt = 1; cCnt <= range.Columns.Count; cCnt++)
        {
            str = (string)(range.Cells[rCnt, cCnt] as Excel.Range).Value2;
            MessageBox.Show(str);
        }
    }
     */
    xlWorkSheet..EntireRow.Delete(Excel.XLDirection.xlUp)
    xlWorkBook.SaveAs(xlWorkBook.Path + @"'XMLCopy.xls",         Excel.XlFileFormat.xlXMLSpreadsheet, Type.Missing, Type.Missing,
   false, false, Excel.XlSaveAsAccessMode.xlNoChange,
   Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
    xlWorkBook.Close(true, null, null);
    xlApp.Quit();
    releaseObject(xlWorkSheet);
    releaseObject(xlWorkBook);
    releaseObject(xlApp);
}
private void releaseObject(object obj)
{
    try
    {
        System.Runtime.InteropServices.Marshal.ReleaseComObject(obj);
        obj = null;
    }
    catch (Exception ex)
    {
        obj = null;
        MessageBox.Show("Unable to release the Object " + ex.ToString());
    }
    finally
    {
        GC.Collect();
    }
}

我如何确保即使在工作簿打开后出现错误，我也能确保处理对象：

Excel.Application xlApp;
Excel.Workbook xlWorkBook;
Excel.Worksheet xlWorkSheet;
Excel.Range range;

换句话说，无论我需要以下几行来运行

xlWorkBook.Close(true, null, null);
xlApp.Quit();
releaseObject(xlWorkSheet);
releaseObject(xlWorkBook);
releaseObject(xlApp);

请注意，我也尝试过，导致了相同的问题

xlWorkBook.Close(false, System.Reflection.Missing.Value, System.Reflection.Missing.Value);

                xlApp.Quit();
                Marshal.ReleaseComObject(xlWorkSheet);
                Marshal.ReleaseComObject(xlWorkBook);
                Marshal.ReleaseComObject(xlApp);
                xlWorkSheet = null;
                xlWorkBook = null;
                xlApp = null;
                GC.GetTotalMemory(false);
                GC.Collect();
                GC.WaitForPendingFinalizers();
                GC.Collect();
                GC.GetTotalMemory(true);  

我也这样做了：

GC.Collect()                   ;
                GC.WaitForPendingFinalizers();
                GC.Collect()                  ; 
                GC.WaitForPendingFinalizers();
                Marshal.FinalReleaseComObject(xlWorkSheet);
                xlWorkBook.Close(Type.Missing, Type.Missing, Type.Missing);
                Marshal.FinalReleaseComObject(xlWorkBook); 
                xlApp.Quit();
                Marshal.FinalReleaseComObject(xlApp); 

在这一点上，我认为从visualstudio2008关闭excel是不可能的。这一定是一个bug或什么的，但我已经尝试了这方面的前20个网站，得到了相同的结果：excel由于某种原因打开了两个实例，当我进行垃圾收集等操作时。（或不）它只关闭了一个实例。

当我试图打开文件时，它会显示有错误或已损坏。

当我去任务管理器并终止excel进程时，文件将毫无问题地打开。]

有没有办法用visualstudio2008关闭excel？如果是的话，你能为我提供这个的指导或解决方案吗