我在C#（ApplicationClass）中使用Excel互操作，并在finally子句中放置了以下代码：
while (System.Runtime.InteropServices.Marshal.ReleaseComObject(excelSheet) != 0) { }
excelSheet = null;
GC.Collect();
GC.WaitForPendingFinalizers();
尽管这种方法有效，但即使在我关闭Excel之后，Excel.exe进程仍处于后台。它只在我的应用程序被手动关闭后发布。
我做错了什么，或者是否有其他方法可以确保正确处理互操作对象？
当前回答
我找到了一个有用的通用模板，它可以帮助实现COM对象的正确处置模式，这些对象在超出范围时需要调用Marshal.ReleaseComObject：
用法：
using (AutoReleaseComObject<Application> excelApplicationWrapper = new AutoReleaseComObject<Application>(new Application()))
{
try
{
using (AutoReleaseComObject<Workbook> workbookWrapper = new AutoReleaseComObject<Workbook>(excelApplicationWrapper.ComObject.Workbooks.Open(namedRangeBase.FullName, false, false, missing, missing, missing, true, missing, missing, true, missing, missing, missing, missing, missing)))
{
// do something with your workbook....
}
}
finally
{
excelApplicationWrapper.ComObject.Quit();
}
}
模板：
public class AutoReleaseComObject<T> : IDisposable
{
private T m_comObject;
private bool m_armed = true;
private bool m_disposed = false;
public AutoReleaseComObject(T comObject)
{
Debug.Assert(comObject != null);
m_comObject = comObject;
}
#if DEBUG
~AutoReleaseComObject()
{
// We should have been disposed using Dispose().
Debug.WriteLine("Finalize being called, should have been disposed");
if (this.ComObject != null)
{
Debug.WriteLine(string.Format("ComObject was not null:{0}, name:{1}.", this.ComObject, this.ComObjectName));
}
//Debug.Assert(false);
}
#endif
public T ComObject
{
get
{
Debug.Assert(!m_disposed);
return m_comObject;
}
}
private string ComObjectName
{
get
{
if(this.ComObject is Microsoft.Office.Interop.Excel.Workbook)
{
return ((Microsoft.Office.Interop.Excel.Workbook)this.ComObject).Name;
}
return null;
}
}
public void Disarm()
{
Debug.Assert(!m_disposed);
m_armed = false;
}
#region IDisposable Members
public void Dispose()
{
Dispose(true);
#if DEBUG
GC.SuppressFinalize(this);
#endif
}
#endregion
protected virtual void Dispose(bool disposing)
{
if (!m_disposed)
{
if (m_armed)
{
int refcnt = 0;
do
{
refcnt = System.Runtime.InteropServices.Marshal.ReleaseComObject(m_comObject);
} while (refcnt > 0);
m_comObject = default(T);
}
m_disposed = true;
}
}
}
参考：
http://www.deez.info/sengelha/2005/02/11/useful-idisposable-class-3-autoreleasecomobject/
其他回答
为了说明Excel不关闭的原因，即使在读取和创建时为每个对象创建直接引用，也需要使用“For”循环。
For Each objWorkBook As WorkBook in objWorkBooks 'local ref, created from ExcelApp.WorkBooks to avoid the double-dot
objWorkBook.Close 'or whatever
FinalReleaseComObject(objWorkBook)
objWorkBook = Nothing
Next
'The above does not work, and this is the workaround:
For intCounter As Integer = 1 To mobjExcel_WorkBooks.Count
Dim objTempWorkBook As Workbook = mobjExcel_WorkBooks.Item(intCounter)
objTempWorkBook.Saved = True
objTempWorkBook.Close(False, Type.Missing, Type.Missing)
FinalReleaseComObject(objTempWorkBook)
objTempWorkBook = Nothing
Next
当上面的所有内容都不起作用时，请尝试给Excel一些时间来关闭工作表：
app.workbooks.Close();
Thread.Sleep(500); // adjust, for me it works at around 300+
app.Quit();
...
FinalReleaseComObject(app);
我完全遵循了这个。。。但我还是遇到了1000次问题中的1次。谁知道为什么。是时候拿出锤子了。。。
在Excel应用程序类实例化之后，我就掌握了刚刚创建的Excel进程。
excel = new Microsoft.Office.Interop.Excel.Application();
var process = Process.GetProcessesByName("EXCEL").OrderByDescending(p => p.StartTime).First();
然后，在完成上述所有COM清理之后，我确保该进程没有运行。如果它还在运行，就杀了它！
if (!process.HasExited)
process.Kill();
我的解决方案
[DllImport("user32.dll")]
static extern int GetWindowThreadProcessId(int hWnd, out int lpdwProcessId);
private void GenerateExcel()
{
var excel = new Microsoft.Office.Interop.Excel.Application();
int id;
// Find the Excel Process Id (ath the end, you kill him
GetWindowThreadProcessId(excel.Hwnd, out id);
Process excelProcess = Process.GetProcessById(id);
try
{
// Your code
}
finally
{
excel.Quit();
// Kill him !
excelProcess.Kill();
}
Excel命名空间中的任何内容都需要发布。时期
你不能这样做：
Worksheet ws = excel.WorkBooks[1].WorkSheets[1];
你必须这样做
Workbooks books = excel.WorkBooks;
Workbook book = books[1];
Sheets sheets = book.WorkSheets;
Worksheet ws = sheets[1];
随后释放物体。
