如何使弹出窗口显示一条消息，然后在5秒钟后显示下载内容，然后关闭弹出窗口

Question

In my project, I have a file that I want the user to download. When they click on the link, I want a popup window to display "Your download will shortly, if it doesn't start click here". After a few seconds, it will then close and the actual file download will then display.

I know to achieve the window closing you'll use:

window.setTimeout(function(){window.close()}, 5000);

But I'm not sure how you would call the download once the window has closed?

Cheers for any help!

Answer 1

Okay so I don't know your platform so will give an ASP.NET version. If you are using something else then I have commented so you should be able to adapt to your platform.

EDIT: Now know user is using PHP so added code snippet for PHP (not robust but I'm no PHP dev)...

1) SAME FOR PHP/ASP Are you getting a file that will not be displayed by the browser automatically? ie .js will be shown as is but an exe will probably trigger a file download dialog (someone correct me if wrong please and I'll update)

If your files are always going to be ie .exe then you could probably just get away with:

$("body").append("<iframe src='http://www.targetsite.com/files/thefilename.exe'></iframe>");

but more likely you will be using a parameter to find the right file (and hide direct download

$("body").append("<iframe src='http://www.targetsite.com/downloader/?file=1234-1234-1234'></iframe>");

in some setTimeout function.

If the filetypes are unknown then I suggest pointing the above code at a script file (.ashx, php, etc) that writes the file byte stream to the http response.

FOR PHP:

<?php    // Demo - send a (binary) file

$file = "ireland.jpg";//here you would use the query string parameter of the above
                      //ajax/iframe request eg file=1234-1234-1234 to find image in db
$fp = fopen($file,"r") ;

header("Content-Type: image/jpeg");//this would need to be modified to either show right content type or you could
                                   //set it to Application/force-download

while (! feof($fp)) {
       $buff = fread($fp,4096);
       print $buff;
       }
?>

WARNING Be careful with the above code. It occurred to me you might pass in filename directly which I'm pretty sure someone could use to get files in other places in your app without careful attention

FOR ASP:

I have included an example ashx (generic handler) solution:

aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Wardle.PdfGenerator;
using System.IO;

public partial class user_account_iframedownloader : System.Web.UI.Page
{
    private IInformixRepository _rep;
    //this page gets loaded into an iframe so we can do downloads while using ajax
    protected void Page_Load(object sender, EventArgs e)
    {
         //write bytes out here i.e. see after for methods

    }
}

Example byte output methods (you just need to do File.getBytes or something - my code is quite complicated so 'excercise for reader'

public static void PdfOutput(byte[] pdfData, string filename)
{
    HttpContext.Current.Response.ContentType = "Application/pdf";
    HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=\"" + filename);
    HttpContext.Current.Response.BinaryWrite(pdfData);
}
public static void PdfZipOutput(byte[] zipData, string filename)
{
    HttpContext.Current.Response.ContentType = "Application/zip";
    HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=\"" + filename);
    HttpContext.Current.Response.BinaryWrite(zipData);
}

Answer 2

In simple way, use window.open() to start download file.

<a href="myfile.doc" id="download">Direct link</a>

<script type="text/javascript">
    setTimeout(function() {
        window.open("myfile.doc");
    },3000);
</script>