使用itextsharp从ashx处理程序保存PDF

Question

我在使用处理程序保存pdf时遇到问题。 当我直接从aspx页面的后端使用时，cs文件正常保存。 但是，当我尝试从ashx处理程序运行代码时，什么也没发生。 我的代码：

public void ProcessRequest(HttpContext context)
    {
 HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.ContentType = "application/pdf";
            HttpContext.Current.Response.AddHeader("content-                   disposition", "attachment;filename=john.pdf");
                                                                              HttpContext.Current.Response.Cache.SetCacheability                                 (HttpCacheability.NoCache);
            StringWriter stringWriter = new StringWriter();
            HtmlTextWriter htmlTextWriter = new HtmlTextWriter(stringWriter);

            string imagepath = context.Server.MapPath(@"~/img/logo3.png");
            Document Doc = new Document(PageSize.A4, 10f, 10f, 10f, 10f);
            HTMLWorker htmlparser = new HTMLWorker(Doc);
            PdfWriter pdfwriter = PdfWriter.GetInstance(Doc, HttpContext.Current.Response.OutputStream);
            Doc.Open();
            iTextSharp.text.Image image = iTextSharp.text.Image.GetInstance(imagepath);
            image.ScalePercent(106f, 90f);
            Doc.Add(image);
            AddPDf(pdfwriter, Doc);
            OnEndPage(pdfwriter, Doc);
            Doc.Close();
             HttpContext.Current.Response.End();
            }

 public void AddPDf(PdfWriter writer, Document document)
 {
 PdfPTable table = new PdfPTable(3);
 table.TotalWidth = 400f;
//fix the absolute width of the table
table.LockedWidth = true;
//relative col widths in proportions - 1/3 and 2/3
float[] widths = new float[] { 2f, 4f, 6f };
table.SetWidths(widths);
table.HorizontalAlignment = 0;
//leave a gap before and after the table
 table.SpacingBefore = 20f;
  table.SpacingAfter = 30f;
 PdfPCell cell = new PdfPCell(new Phrase("Header spanning 3 columns"));
 cell.Colspan = 3;
 cell.HorizontalAlignment = 1; //0=Left, 1=Centre, 2=Right
 table.AddCell(cell);
 table.AddCell("Col 1 Row 1");
  table.AddCell("Col 2 Row 1");
  table.AddCell("Col 3 Row 1");
  table.AddCell("Col 1 Row 2");
  table.AddCell("Col 2 Row 2");
  table.AddCell("Col 3 Row 2");
 document.Open();
 document.Add(table);
    }
    public void OnEndPage(PdfWriter writer, Document document)
    {


        var content = writer.DirectContent;
        var pageBorderRect = new Rectangle(document.PageSize);

        pageBorderRect.Left += document.LeftMargin;
        pageBorderRect.Right -= document.RightMargin;
        pageBorderRect.Top -= document.TopMargin;
        pageBorderRect.Bottom += document.BottomMargin;

        content.SetColorStroke(BaseColor.BLACK);
        content.Rectangle(pageBorderRect.Left, pageBorderRect.Bottom, pageBorderRect.Width, pageBorderRect.Height);
        content.Stroke();
    }
    private static void addCell(PdfPTable table, string text, int rowspan)
    {
        BaseFont bfTimes = BaseFont.CreateFont(BaseFont.TIMES_ROMAN, BaseFont.CP1252, false);
        iTextSharp.text.Font times = new iTextSharp.text.Font(bfTimes, 6, iTextSharp.text.Font.NORMAL, iTextSharp.text.BaseColor.BLACK);

        PdfPCell cell = new PdfPCell(new Phrase(text, times));
        cell.Rowspan = rowspan;
        cell.HorizontalAlignment = PdfPCell.ALIGN_CENTER;
        cell.VerticalAlignment = PdfPCell.ALIGN_MIDDLE;
        table.AddCell(cell);
    }

Answer 1

您可以这样导出pdf：

作为链接：

<a target="_blank" href="/exportPDF.ashx">Export PDF</a>

作为javascript函数：

    function exportPDF() {
        location.href = "/exportPDF.ashx";
    }

Javascript会进行重定向，但是由于响应是文件，因此浏览器将提示您执行操作（打开/保存）并停留在同一页面上。

您的代码确实会生成PDF，因此您可以按原样使用它。