如何删除Excel互操作对象，我使用EXCEL互操作在C＃应用程序

Question

参考genearting Excel，然后我附上它作为附件邮寄，然后发送邮件mail.After发送我想删除生成的文件。在删除它抛出错误：

this file cannot be deleted as it is is used by another process 

我搜索了SO等网站，发现有关COM组件有趣的事实。
参考： - How do I properly clean up Excel interop objects?

如果我不附加它作为附件然后文件被删除。在删除之前，我删除所有COM references.but当我使用它作为附件它抛出错误： 我的代码是这样的：

workbook.SaveAs(root + statics + ".xls", Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlNoChange, 
        Type.Missing, Type.Missing, Type.Missing, Type.Missing); 

        // Garbage collecting 
        // Clean up references to all COM objects 
        // As per above, you're just using a Workbook and Excel Application instance, so release them: 
        GC.Collect(); 
        GC.WaitForPendingFinalizers(); 
        Marshal.FinalReleaseComObject(m_objRange); 

        Marshal.FinalReleaseComObject(worksheet); 
        workbook.Close(false, Type.Missing, Type.Missing); 
        Marshal.FinalReleaseComObject(workbook); 
        app.Quit(); 
        Marshal.FinalReleaseComObject(app); 

        MailMessage mm = new MailMessage("def@gmail.com", "xyz@gmail.com", "TestMsg", "Hi"); 
        SmtpClient client = new SmtpClient("smtp.gmail.com", 587); 
        client.Credentials = CredentialCache.DefaultNetworkCredentials; 

        //Commenting Below two lines works fine ....!!!!!!!!!....WHY..??? 

        //Attachment data = new Attachment(root + statics + ".xls"); 
        //mm.Attachments.Add(data); 

        client.Send(mm); 

        File.Delete(root + statics + ".xls"); 

如何安装它邮寄后删除引用。 感谢

Answer 1

发送邮件后，只是增加data.Dispose（）工作正常进行me.here修改代码：

workbook.SaveAs(root + statics + ".xls", Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlNoChange, 
        Type.Missing, Type.Missing, Type.Missing, Type.Missing); 

        // Garbage collecting 
        // Clean up references to all COM objects 
        // As per above, you're just using a Workbook and Excel Application instance, so release them: 
        GC.Collect(); 
        GC.WaitForPendingFinalizers(); 
        Marshal.FinalReleaseComObject(m_objRange); 

        Marshal.FinalReleaseComObject(worksheet); 
        workbook.Close(false, Type.Missing, Type.Missing); 
        Marshal.FinalReleaseComObject(workbook); 
        app.Quit(); 
        Marshal.FinalReleaseComObject(app); 

        MailMessage mm = new MailMessage("def@gmail.com", "xyz@gmail.com", "TestMsg", "Hi"); 
        SmtpClient client = new SmtpClient("smtp.gmail.com", 587); 
        client.Credentials = CredentialCache.DefaultNetworkCredentials; 


        Attachment data = new Attachment(root + statics + ".xls"); 
        mm.Attachments.Add(data); 
        //Now Working Fine:- 
        data.Dispose(); 
        client.Send(mm); 

        File.Delete(root + statics + ".xls"); 

Answer 2

MAILMESSAGE的和SmtpClient应布置，这样做，MAILMESSAGE的，也作主任何附件。

using(SmtpClient client = new SmtpClient("smtp.gmail.com", 587)) 
using(MailMessage mm = new MailMessage("def@gmail.com", "xyz@gmail.com", "TestMsg", "Hi")) 
{ 

    client.Credentials = CredentialCache.DefaultNetworkCredentials; 
    client.Send(mm); 
}