Force to open “Save As…” popup open at text link c

2018-12-31 20:35发布

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可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

I have some big size PDF catalogs at my website, and I need to link these as download. When I googled, I found such a thing noted below. It should open the \"Save As...\" popup at link click...

 <head>
    <meta name=\"content-disposition\" content=\"inline; filename=filename.pdf\">
    ...

But it doesn\'t work :/ When I link to a file as below, it just links to file and is trying to open the file.

    <a href=\"filename.pdf\" title=\"Filie Name\">File name</a>

UPDATE (according to answers below):

As I see there is no 100% reliable cross-browser solution for this. Probably the best way is using one of the web services listed below, and giving a download link...

http://box.net/
http://droplr.com/
http://getcloudapp.com/

回答1:

From an answer to Force a browser to save file as after clicking link:

<a href=\"path/to/file\" download>Click here to download</a>

回答2:

<a href=\"file link\" download target=\"_blank\">Click here to download</a>

It works for me in Firefox and Chrome.

回答3:

Meta tags are not a reliable way to achieve this result. Generally you shouldn\'t even do this - it should be left up to the user/user agent to decide what do to with the content you provide. The user can always force their browser to download the file if they wish to.

If you still want to force the browser to download the file, modify the HTTP headers directly. Here\'s a PHP code example:

$path = \"path/to/file.pdf\";
$filename = \"file.pdf\";
header(\'Content-Transfer-Encoding: binary\');  // For Gecko browsers mainly
header(\'Last-Modified: \' . gmdate(\'D, d M Y H:i:s\', filemtime($path)) . \' GMT\');
header(\'Accept-Ranges: bytes\');  // Allow support for download resume
header(\'Content-Length: \' . filesize($path));  // File size
header(\'Content-Encoding: none\');
header(\'Content-Type: application/pdf\');  // Change the mime type if the file is not PDF
header(\'Content-Disposition: attachment; filename=\' . $filename);  // Make the browser display the Save As dialog
readfile($path);  // This is necessary in order to get it to actually download the file, otherwise it will be 0Kb

Note that this is just an extension to the HTTP protocol; some browsers might ignore it anyway.

回答4:

I had this same issue and found a solution that has worked great so far. You put the following code in your .htaccess file:

<FilesMatch \"\\.(?i:pdf)$\">
  ForceType application/octet-stream
  Header set Content-Disposition attachment
</FilesMatch>

It came from Force a File to Download Instead of Showing Up in the Browser.

回答5:

I found a very simple solution for Firefox (only works with a relative rather than a direct href): add type=\"application/octet-stream\":

<a href=\"./file.pdf\" id=\'example\' type=\"application/octet-stream\">Example</a>

回答6:

Try adding this line to your .htaccess file.

AddType application/octet-stream .pdf

I hope it\'ll work as it is browser independent.

回答7:

Generally it happens, because some browsers settings or plug-ins directly open PDF in the same window like a simple web page.

The following might help you. I have done it in PHP a few years back. But currently I\'m not working on that platform.

<?php
    if (isset($_GET[\'file\'])) {
        $file = $_GET[\'file\'];
        if (file_exists($file) && is_readable($file) && preg_match(\'/\\.pdf$/\',$file)) {
            header(\'Content-type: application/pdf\');
            header(\"Content-Disposition: attachment; filename=\\\"$file\\\"\");
            readfile($file);
        }
    }
    else {
        header(\"HTTP/1.0 404 Not Found\");
        echo \"<h1>Error 404: File Not Found: <br /><em>$file</em></h1>\";
    }
?>

Save the above as download.php.

Save this little snippet as a PHP file somewhere on your server and you can use it to make a file download in the browser, rather than display directly. If you want to serve files other than PDF, remove or edit line 5.

You can use it like so:

Add the following link to your HTML file.

<a href=\"download.php?file=my_pdf_file.pdf\">Download the cool PDF.</a>

Reference from: This blog

回答8:

A really simple way to achieve this, without using external download sites or modifying headers etc. is to simply create a ZIP file with the PDF inside and link directly to the ZIP file. This will ALWAYS trigger the Save/Open dialog, and it\'s still easy for people to double-click the PDF windows the program associated with .zip is launched.

BTW great question, I was looking for an answer as well, since most browser-embedded PDF plugins take sooo long to display anything (and will often hang the browser whilst the PDF is loading).

回答9:

A very easy way to do this, if you need to force download for a single link on your page, is to use the HTML5 download-attribute in the href-link.

See: http://davidwalsh.name/download-attribute

with this you can rename the file that the user will download and at the same time it forces the download.

There has been a debate whether this is good practise or not, but in my case I have an embedded viewer for a pdf file and the viewer does not offer a download link, so i have to provide one separately. Here I want to make sure the user does not get the pdf opened in the web browser, which would be confusing.

This won\'t necessary open the save as-dialog, but will download the link straight to the preset download destination. And of course if your doing a site for someone else, and need them to write in manually attributes to their links is probably a bad idea, but if there is way to get the attribute into the links, this can be a light solution.

回答10:

Just put the below code in your .htaccess file:

AddType application/octet-stream .csv
AddType application/octet-stream .xls
AddType application/octet-stream .doc
AddType application/octet-stream .avi
AddType application/octet-stream .mpg
AddType application/octet-stream .mov
AddType application/octet-stream .pdf

Or you can also do trick by JavaScript

element.setAttribute( \'download\', whatever_string_you_want);

回答11:

I just used this, but I don\'t know if it works across all browsers.

It works in Firefox:

<a href=\"myfile.pdf\" download>Click to Download</a>

回答12:

A server-side solution is more compatible, until the \"download\" attribute is implemented in all the browsers.

One Python example could be a custom HTTP request handler for a filestore. The links that point to the filestore are generated like this:

http://www.myfilestore.com/filestore/13/130787e71/download_as/desiredName.pdf

Here is the code:

class HTTPFilestoreHandler(SimpleHTTPRequestHandler):

    def __init__(self, fs_path, *args):
        self.fs_path = fs_path                          # Filestore path
        SimpleHTTPRequestHandler.__init__(self, *args)

    def send_head(self):
        # Overwrite SimpleHTTPRequestHandler.send_head to force download name
        path = self.path
        get_index = (path == \'/\')
        self.log_message(\"path: %s\" % path)
        if \'/download_as/\' in path:
            p_parts = path.split(\'/download_as/\')
            assert len(p_parts) == 2, \'Bad download link:\' + path
            path, download_as = p_parts
        path = self.translate_path(path )
        f = None
        if os.path.isdir(path):
            if not self.path.endswith(\'/\'):
                # Redirect browser - doing basically what Apache does
                self.send_response(301)
                self.send_header(\"Location\", self.path + \"/\")
                self.end_headers()
                return None
            else:
                return self.list_directory(path)
        ctype = self.guess_type(path)
        try:
            f = open(path, \'rb\')
        except IOError:
            self.send_error(404, \"File not found\")
            return None
        self.send_response(200)
        self.send_header(\"Content-type\", ctype)
        fs = os.fstat(f.fileno())
        self.send_header(\"Expires\", \'0\')
        self.send_header(\"Last-Modified\", self.date_time_string(fs.st_mtime))
        self.send_header(\"Cache-Control\", \'must-revalidate, post-check=0, pre-check=0\')
        self.send_header(\"Content-Transfer-Encoding\", \'binary\')
        if download_as:
            self.send_header(\"Content-Disposition\", \'attachment; filename=\"%s\"\' % download_as)
        self.send_header(\"Content-Length\", str(fs[6]))
        self.send_header(\"Connection\", \'close\')
        self.end_headers()
        return f


class HTTPFilestoreServer:

    def __init__(self, fs_path, server_address):
        def handler(*args):
            newHandler = HTTPFilestoreHandler(fs_path, *args)
            newHandler.protocol_version = \"HTTP/1.0\"
        self.server = BaseHTTPServer.HTTPServer(server_address, handler)

    def serve_forever(self, *args):
        self.server.serve_forever(*args)


def start_server(fs_path, ip_address, port):
    server_address = (ip_address, port)
    httpd = HTTPFilestoreServer(fs_path, server_address)

    sa = httpd.server.socket.getsockname()
    print \"Serving HTTP on\", sa[0], \"port\", sa[1], \"...\"
    httpd.serve_forever()

回答13:

After the file name in the HTML code I add ?forcedownload=1

This has been the simplest way for me to trigger a dialog box to save or download.

回答14:

If you have a plugin within the browser which knows how to open a PDF file it will open directly. Like in case of images and HTML content.

So the alternative approach is not to send your MIME type in the response. In this way the browser will never know which plugin should open it. Hence it will give you a Save/Open dialog box.

回答15:

I just had a very similar issue with the added problem that I needed to create download links to files inside a ZIP file.

I first tried to create a temporary file, then provided a link to the temporary file, but I found that some browsers would just display the contents (a CSV Excel file) rather than offering to download. Eventually I found the solution by using a servlet. It works both on Tomcat and GlassFish, and I tried it on Internet Explorer 10 and Chrome.

The servlet takes as input a full path name to the ZIP file, and the name of the file inside the zip that should be downloaded.

Inside my JSP file I have a table displaying all the files inside the zip, with links that say: onclick=\'download?zip=<%=zip%>&csv=<%=csv%>\'

The servlet code is in download.java:

package myServlet;

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.zip.*;
import java.util.*;

// Extend HttpServlet class
public class download extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException
    {
        PrintWriter out = response.getWriter(); // now we can write to the client

        String filename = request.getParameter(\"csv\");
        String zipfile = request.getParameter(\"zip\");

        String aLine = \"\";

        response.setContentType(\"application/x-download\");
        response.setHeader( \"Content-Disposition\", \"attachment; filename=\" + filename); // Force \'save-as\'
        ZipFile zip = new ZipFile(zipfile);
        for (Enumeration e = zip.entries(); e.hasMoreElements();) {
            ZipEntry entry = (ZipEntry) e.nextElement();
            if(entry.toString().equals(filename)) {
                InputStream is = zip.getInputStream(entry);
                BufferedReader br = new BufferedReader(new InputStreamReader(is, \"UTF-8\"), 65536);
                while ((aLine = br.readLine()) != null) {
                    out.println(aLine);
                }
                is.close();
                break;
            }
        }
    }
}

To compile on Tomcat you need the classpath to include tomcat\\lib\\servlet-api.jar or on GlassFish: glassfish\\lib\\j2ee.jar

But either one will work on both. You also need to set your servlet in web.xml.

回答16:

This is old post but here is the one my solution in JavaScript what using jQuery library.

<script>
(function($){
    var download = [];
    $(\'a.force-download, .force-download a\').each(function(){
        // Collect info
        var $this = $(this),
            $href = $this.attr(\'href\'),
            $split = $href.split(\'/\'),
            $name = document.title.replace(/[\\W_]/gi, \'-\').replace(/-{2,}/g, \'-\'); // get title and clean it for the URL

        // Get filename from URL
        if($split[($split.length-1)])
        {
            $tmp = $split[($split.length-1)];
            $tmp = $tmp.split(\'.\');
            $name = $tmp[0].replace(/[\\W_]/gi, \'-\').replace(/-{2,}/g, \'-\');
        }

        // If name already exists, put timestamp there
        if($.inArray($name, download) > -1)
        {
            $name = $name + \'-\' + Date.now().replace(/[\\W]/gi, \'-\');
        }

        $(this).attr(\"download\", $name);
        download.push($name);
    });
}(jQuery || window.jQuery))
</script>

You just need to use class force-download inside your <a> tag and will force download automaticaly. You also can add it to parent div and will pickup all links inside it.

Example:

<a href=\"/some/good/url/Post-Injection_Post-Surgery_Instructions.pdf\" class=\"force-download\" target=\"_blank\">Download PDF</a>

This is great for WordPress and any other systems or custom websites.

回答17:

With large PDF files the browser hangs. In Mozilla, menu Tools → Options → Applications, then next to the content type Adobe Acrobat document. In the Action drop down, select Always ask.

This did not work for me, so what worked was:

Menu Tools* → Add-ons → Adobe Acrobat (Adobe PDF plugin for Firefox) → DISABLE. Now I am able to download e-books!

标签： html pdf download meta-tags content-disposition