将多个pdf下载到zip文件夹中

Question

所以我试图一次将所有已付款发票下载为 pdf。但是当我下载一张发票时，代码可以工作，但对于多张发票，它返回错误 500。

多张发票代码

public ActionResult ExportAndDownloadAllCROInvoices(int CROID)
{
    var listInvoices = new VM_Invoice().FindAllByAttributes(x => x.CreatedForId == CROID && x.CreatedForType == (int)UserTypes.CRO && x.IsPaid == true);

    try
    {
        string folderPath = Server.MapPath("~/PDFInvoices/");
        if (!Directory.Exists(folderPath))
        {
            Directory.CreateDirectory(folderPath);
        }

        List<string> filePaths = new List<string>();

        foreach (var invoiceModel in listInvoices)
        {
            string htmlString = string.Empty;
            if (invoiceModel.CreatedForType == (int)UserTypes.CRO)
            {
                htmlString = new VM_Invoice().GetCROInvoiceHtmlTemplate(invoiceModel);
            }

            byte[] fileBytes = PDFUtilities.ExportInvoicePDF(htmlString);
            string fileName = string.Format("Invoice-{0}-{1}.pdf", invoiceModel.InvoiceNo, DateTime.UtcNow.ToString("MMddyyyy"));
            string filePath = Path.Combine(folderPath, fileName);
            System.IO.File.WriteAllBytes(filePath, fileBytes);

            filePaths.Add(filePath);
        }

        // Create a zip archive containing all PDF invoices
        string zipPath = Path.Combine(Server.MapPath("~/PDFInvoices/"), "Invoices.zip");
        ZipFile.CreateFromDirectory(folderPath, zipPath);

        // Clean up individual PDF files
        foreach (var filePath in filePaths)
        {
            System.IO.File.Delete(filePath);
        }

        // Return the zip archive as a downloadable file
        return File(System.IO.File.ReadAllBytes(zipPath), "application/zip", "Invoices.zip");
    }
    catch (Exception ex)
    {
        ViewBag.ErrorMessage = "An error occurred while generating and downloading PDF invoices.";
        return RedirectToAction("WorkLogReport", "ControllerName");
    }
}

单一发票代码

public ActionResult ExportPDFInvoice(int id)
{
    string htmlString = string.Empty;
    try
    {
        VM_Invoice invoiceModel = new VM_Invoice().FindById(id);
        if (invoiceModel.CreatedForType == (int)UserTypes.Consumer)
        {
            htmlString = new VM_Invoice().GetConsumerInvoiceHtmlTemplate(invoiceModel);
        }
        else
        {
            htmlString = new VM_Invoice().GetCROInvoiceHtmlTemplate(invoiceModel);
        }
        byte[] fileBytes = PDFUtilities.ExportInvoicePDF(htmlString);
        string fileName = string.Format("Invoice-{0}.pdf", DateTime.UtcNow.ToString("MMddyyyy"));
        return File(fileBytes, "application/pdf", fileName);
    }
    catch (Exception ex)
    {
        return RedirectToAction("WorkLogReport");
    }
}

Answer 1

如果您已经验证您的过程有效，则错误可能是由于 .pdf 文件和 .zip 文件位于同一目录中，因此 ZipFile 类也尝试压缩它正在创建的存档。尝试使用另一个目标 .zip 目录。