c# - 如何在 HTML 对象标记中呈现 PDF 字节数组

Question

我有一个由 ASPose 生成的字节数组形式的 PDF，我想在网页上的组件内部呈现该 PDF。

        using (MemoryStream docStream = new MemoryStream())
        {
            doc.Save(docStream, Aspose.Words.SaveFormat.Pdf);
            documentStream = docStream.ToArray();
        }

我认为这只是将字节数组分配给后面代码中的数据属性的简单变体。下面是设置，以及我尝试过的一些变体。我该怎么做才能将该字节数组呈现为网页的可见子组件？

       HtmlGenericControl pTag = new HtmlGenericControl("p");
        pTag.InnerText = "No Letter was Generated.";
        pTag.ID = "errorMsg";
        HtmlGenericControl objTag = new HtmlGenericControl("object");
        objTag.Attributes["id"] = "pdf_content";
        objTag.Attributes["height"] = "400";
        objTag.Attributes["width"] = "500";
        String base64EncodedPdf = System.Convert.ToBase64String(pdfBytes);

        //1-- Brings up the "No Letter was Generated" message
         objTag.Attributes["data"] = "data:application/pdf;base64," + base64EncodedPdf.ToString(); 

        //2-- Brings up the gray PDF background and NO initialization bar.
        objTag.Attributes["type"] = "application/pdf";
        objTag.Attributes["data"] = "data:application/pdf;base64," + base64EncodedPdf.ToString();

        //3-- Brings up the gray PDF background and the initialization bar, then stops.
        objTag.Attributes["type"] = "application/pdf";
        objTag.Attributes["data"] = pdfBytes.ToString();  

        //4-- Brings up a white square of the correct size, containing a circle with a slash in the top left corner.
        objTag.Attributes["data"] = "application/pdf" + pdfBytes.ToString();


        objTag.Controls.Add(pTag);
        pdf.Controls.Add(objTag);

Answer 1

object 的 data 属性标签应包含指向将提供 PDF 字节流的端点的 URL。它不应包含字节流本身内联。

要使此页面正常工作，您需要添加一个额外的 handler提供字节流，例如GetPdf.ashx。处理程序的 ProcessRequest 方法将准备 PDF 字节流并在响应中内联返回它，前面是适当的 header ，表明它是一个 PDF 对象。

protected void ProcessRequest(HttpContext context)
{
    byte[] pdfBytes = GetPdfBytes(); //This is where you should be calling the appropriate APIs to get the PDF as a stream of bytes
    var response = context.Response;
    response.ClearContent();
    response.ContentType = "application/pdf";
    response.AddHeader("Content-Disposition", "inline");
    response.AddHeader("Content-Length", pdfBytes.Length.ToString());
    response.BinaryWrite(pdfBytes); 
    response.End();
}

与此同时，您的主页将使用指向处理程序的 URL 填充 data 属性，例如

objTag.Attributes["data"] = "GetPdf.ashx";