创建pdf文件后，c＃excel不会清理

c# excel does not clean up after creating pdf file

我已使用下面的代码成功地将Excel文件转换为PDF文件。我尝试使用以下方法释放Excel对象。-退出并关闭空值-不要对COM对象使用两个点-释放对象气相色谱收集

但是，任务管理器中仍然保留"excel.exe"。我不想通过调用任务管理器中的进程列表来终止"excel.exe"

我该如何解决这个问题？

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public bool ExportWorkbookToPdf(string workbookPath, string outputPath)
{
// If either required string is null or empty, stop and bail out
if (string.IsNullOrEmpty(workbookPath) || string.IsNullOrEmpty(outputPath))
{
return false;
}

// Create COM Objects
Microsoft.Office.Interop.Excel.Application excelApplication;
Microsoft.Office.Interop.Excel.Workbooks excelWorkbooks;
Microsoft.Office.Interop.Excel.Workbook excelWorkbook;

// Create new instance of Excel
//var excelApplication = new Microsoft.Office.Interop.Excel.Application();
excelApplication = new Microsoft.Office.Interop.Excel.Application();

// Make the process invisible to the user
excelApplication.ScreenUpdating = false;

// Make the process silent
excelApplication.DisplayAlerts = false;

// Open the workbook that you wish to export to PDF
excelWorkbooks = excelApplication.Workbooks;
excelWorkbook = excelWorkbooks.Open(workbookPath);

// If the workbook failed to open, stop, clean up, and bail out
if (excelWorkbook == null)
{
//excelApplication.Application.Quit();
excelApplication.Quit();

excelWorkbook = null;
excelWorkbooks = null;
excelApplication = null;

return false;
}

var exportSuccessful = true;
try
{
excelWorkbook.ExportAsFixedFormat(Microsoft.Office.Interop.Excel.XlFixedFormatType.xlTypePDF, outputPath);
}
catch (System.Exception ex)
{
// Mark the export as failed for the return value...
exportSuccessful = false;

// Do something with any exceptions here, if you wish...
// MessageBox.Show...
}
finally
{
// Close the workbook, quit the Excel, and clean up regardless of the results...
excelWorkbook.Close();
excelWorkbooks.Close();
excelApplication.Quit();

excelWorkbook = null;
excelWorkbooks = null;
excelApplication = null;

ReleaseExcelObject(excelWorkbook);
ReleaseExcelObject(excelWorkbooks);
ReleaseExcelObject(excelApplication);
}
return exportSuccessful;
}
private static void ReleaseExcelObject(object obj)
{
try
{
if (obj != null)
{
Marshal.ReleaseComObject(obj);
obj = null;
}
}
catch (Exception ex)
{
obj = null;
throw ex;
}
finally
{
GC.Collect();
GC.WaitForPendingFinalizers();
GC.Collect();
GC.WaitForPendingFinalizers();
}
}

在finally语句中，在使用相同的引用传递给ReleaseExcelObject之前，将ExcelWorkbooks&ExcelApplication设置为空，因此您实际上是在调用ReleaseExcelObject(空)；它只调用gcCollect。尝试交换订单。

另外，在代码的前面-如果您无法打开工作簿，只需退出应用程序并将引用设置为空。您可以尝试在try语句中打开工作簿，这样就可以在finally语句中清除错误条件，而不需要重复的代码。

沿着这条线的东西：

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