Spire.xls - return 来自流的文件供客户端下载

Spire.xls - return a File from a stream for client download

这是我想要完成的。

我正在创建一个 asp.net MVC 应用程序。我的限制是我无法以编程方式将任何内容保存到服务器的文件结构中,因此我无法将其保存为主机上的物理文件,然后抓取它供客户端下载。

我正在将 PDF 加载到流中,从 PDF 中提取信息,动态构建 excel 文件,然后将该文件提供给客户端供下载。我的代码如下。

    // Loads the incoming PDF document to stream
    PdfDocument doc = new PdfDocument();
    using (var stream = model.BudgetPdfFile.OpenReadStream())
    {
        doc.LoadFromStream(stream);
    }
    
    var pageCount = doc.Pages.Count;
    var date = DateTime.Now.ToShortDateString().Replace("/", "-");
    
    // Extracts data from the PDF and separates it by NewLine
    SimpleTextExtractionStrategy strategy = new SimpleTextExtractionStrategy();
    StringBuilder allText = new StringBuilder();
    for (var i = 0; i < pageCount; i++)
    {
        allText.Append(doc.Pages[i].ExtractText(strategy));
    }
    var fullDocText = allText.ToString();
    List<string> linesList = new List<string>(fullDocText.Split(new[] { Environment.NewLine }, StringSplitOptions.None).ToList());
    
    // generates a comparison list for output data manipulation from static data
    var finalList = linesList.BuildFinalList(budgetItems);
    
    // creates a new Spire.PDF.Workbook for the final output excel file
    var result = new Workbook();
    
    // checks for whether the submitted budget is for a case in litigation or not and builds the correct excel workbook
    if (model.isTrial)
    {
        result = ExportExcelBudget.TrialBudgetSheet(model, finalList);
    }
    else
    {
        result = ExportExcelBudget.PreTrialBudgetSheet(model, finalList);
    }

到下面最后一节为止的所有内容绝对完美。但是,我不知道如何将工作簿加载到新流中,然后 return 下载文件。

    // saves the final workbook to a stream and offers it for download to the client 
    Stream outStream = new MemoryStream();
    var fileName = "Budget Report_" + model.ClaimNumber + "_" + date + ".xlsx";
    var contentType = "application/vnd.ms-excel";
    result.SaveToStream(outStream, Spire.Xls.FileFormat.Version2016);
    
    return File(outStream, contentType, fileName);

我搜索并尝试了多种不同的变体,但是当应用程序访问 return File() 时,它 return 为 null。

我已经逐步执行,结果似乎已经存在,但没有通过任何东西。任何有关这里错误的帮助将不胜感激。

    Stream outStream = new MemoryStream();
    var fileName = "Budget Report_" + model.ClaimNumber + "_" + date + ".xlsx";
    var contentType = "application/vnd.ms-excel";
    result.SaveToStream(outStream, Spire.Xls.FileFormat.Version2016);
    **outStream.Position = 0;**

    return File(outStream, contentType, fileName);

必须将流位置重置为 0。现在工作正常。