Question

Hellow，我尝试创建一个pdf文件，并同时将它们同时循环发送到其他电子邮件地址，但是似乎第一个创建的文件并没有关闭以允许创建下一个文件，我使用了相同的名称（覆盖文件）。

这是附加电子邮件的代码

private void sendEmail(string email)
    {
        sendInfo = new Label();
        sendInfo.Font = new Font("Calibri", 11);


        sendInfo.AutoSize = true;

        MailMessage mail = new MailMessage("ikwabe04@gmail.com", email, "TESTING THE SALARY SLIP EMAIL SENDER", "Habari Rafiki? Usishitushwe na ujumbe huu, tunajaribu system. Asante.");
        SmtpClient client = new SmtpClient("smtp.gmail.com");
        client.Port = 587;

        client.Credentials = new System.Net.NetworkCredential("ikwabe04@gmail.com", "mikunjoyamwili");
        client.EnableSsl = true;

            Attachment file = new Attachment("C:/Users/" + Home.computerName + "/AppData/Roaming/SEC Payroll/Receipts/receipt.pdf");
            file.Name = "Salary Slip for " + DateTime.Now.ToString("MMMM yyyy") + ".pdf";
            mail.Attachments.Add(file);

        try
        {
            client.Send(mail);
            Login.RecordUserActivity("Sent the Salary Slip to " + email);

            sendInfo.ForeColor = Color.LightGreen;
            sendInfo.Text = "Email sent to: " + email + "     (" + DateTime.Now.ToLongTimeString() + ")";
            information.Controls.Add(sendInfo);
        }
        catch
        {
            sendInfo.ForeColor = Color.Orange;
            sendInfo.Text = "Email NOT sent to: " + email + "     ("+DateTime.Now.ToLongTimeString()+")";
            information.Controls.Add(sendInfo);
        }


    }

此处创建PDF的代码

using (FileStream file = new FileStream("C:/Users/" + Home.computerName + "/AppData/Roaming/SEC Payroll/Receipts/receipt.pdf", FileMode.Create))
            {
                Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 10f);
                PdfWriter.GetInstance(pdfDoc, file);
            pdfDoc.Open();
            pdfDoc.Add(table);
            pdfDoc.Add(slp);
            pdfDoc.Add(Separator);

            pdfDoc.Add(table1);
            pdfDoc.Add(Separator);
            pdfDoc.Add(Tsh);
            pdfDoc.Add(incomeTitle);
            pdfDoc.Add(incomeTable);
            pdfDoc.Add(totaInc);
            pdfDoc.Add(taxDeductionTitle);
            pdfDoc.Add(taxDeduction);
            pdfDoc.Add(otherDeductionTitle);
            pdfDoc.Add(OtherDeduction);
            pdfDoc.Add(totaDeduc);
            pdfDoc.Close();
            file.Close();
        }

这是发送电子邮件的代码

for (int i = 0; i< table.Rows.Count;i++)
{
    PreapareSalarySlip(table.Rows[i][2].ToString(),
                       table.Rows[i][3].ToString(),
                       table.Rows[i][5].ToString(),
                       table.Rows[i][37].ToString()
                       );


                 sendEmail(table.Rows[i][38].ToString());      
                }

这里是发生错误的地方 mscorlib.dll中发生了'System.IO.IOException'类型的未处理异常

其他信息：该进程无法访问文件“ C：\ Users \ Shadrack Ikwabe \ AppData \ Roaming \ SEC Payroll \ Receipts \ receipt.pdf”，因为该文件正在被另一个进程使用。

Answer 1

锁定文件的不是PDF创建过程。这是附件。 Attachment类将锁定文件，并且在释放文件之前不会释放该锁定。之所以会出现异常，是因为您试图将同一文件附加到两封不同的电子邮件中，而不通过释放附件来释放锁定。

SmtpClient和MailMessage也是一次性的。处置MailMessage就足够了；当它被处置时，它也会处置其附件。但是，我认为最好使其明确。

您应该使用using妥善处理它们：

using (MailMessage mail = new MailMessage("ikwabe04@gmail.com", email, "TESTING THE SALARY SLIP EMAIL SENDER", "Habari Rafiki? Usishitushwe na ujumbe huu, tunajaribu system. Asante."))
using (SmtpClient client = new SmtpClient("smtp.gmail.com"))
using (Attachment file = new Attachment("C:/Users/" + Home.computerName + "/AppData/Roaming/SEC Payroll/Receipts/receipt.pdf"))
{
    client.Port = 587;
    client.Credentials = new System.Net.NetworkCredential("ikwabe04@gmail.com", "mikunjoyamwili");
    client.EnableSsl = true;      

    file.Name = "Salary Slip for " + DateTime.Now.ToString("MMMM yyyy") + ".pdf";
    mail.Attachments.Add(file);
    try
    {
        client.Send(mail);
        Login.RecordUserActivity("Sent the Salary Slip to " + email);

        sendInfo.ForeColor = Color.LightGreen;
        sendInfo.Text = "Email sent to: " + email + "     (" + DateTime.Now.ToLongTimeString() + ")";
        information.Controls.Add(sendInfo);
    }
    catch
    {
        sendInfo.ForeColor = Color.Orange;
        sendInfo.Text = "Email NOT sent to: " + email + "     ("+DateTime.Now.ToLongTimeString()+")";
        information.Controls.Add(sendInfo);
    }
}

使用C＃将带有循环附件的电子邮件发送到其他电子邮件地址

1 个答案: