ASP.NET下载对话框

Question

I have this code..

<li><a href="downloads/PDF_File.pdf">PDF</a></li>

but it opens the pdf file, now I am new to ASP.NET, how do I get the download dialog box to open?

Answer 1

Check this question:

Download Stream File From URL in ASP.Net

As well as these articles:

File Download in ASP.NET and Tracking the Status of Success/Failure of Download

File downloading in ASP.Net using C#

Answer 2

Basically, what is happening here is the normal behaviour for pdf files. IIS by default serves up the "pdf" MIME-type for any pdf files in your web application. When you access a pdf in your application, the browser reads the MIME-type and understands that you are accessing a pdf file.. most browsers will want to display it in their built-in PDF reader instead of prompting you to save it. If you really need a download dialog box to show up for pdfs, you could change the MIME-type for pdf in web.config so that IIS will serve up pdfs as a basic filetype within your application:

<configuration>
    <system.webServer>
        <staticContent>
            <remove fileExtension=".pdf" />
            <mimeMap fileExtension=".pdf" mimeType="application/octet-stream" />
        </staticContent>
    </system.webServer>
</configuration>

Note: You should first remove the MIME-type you are manually setting in web.config, because a MIME-type for the same extension may already be set at the application level.

Now IIS will serve up pdf files as a basic/unknown filetype and they will be downloadable. This works for any filetype if you just swap out '.pdf' for a different extension.

Answer 3

I don't know how to do this with existing files, but a while ago I wrote a piece of code combining iTextSharp and an ASP.net (framework 4) MemoryStream object to create then download pdf files, I hope this could be helpful :

MemoryStream msPDF = new MemoryStream();
// do some stuff with iTextSharp ...
Response.ContentType = "application/pdf";
Response.AppendHeader("Content-Disposition", "attachment; filename=myPdf.pdf"); // open/save dialog
Response.BinaryWrite(msPDF.ToArray());