Multiple files download visual force

Question

I have a requirement to download multiple files on a click of visual force button.

i know below will work if its a single file

<a href="/servlet/servlet.FileDownload?file={!Documents}">

any clue about how to gain this for multiple files

Answer 1

There is no way standard way to achieve this goal. Apex Code doesn't have native "compressed file" APIs, so you can't compress the files together easily. HTML doesn't have a specification that allows a single link to represent multiple resources simultaneously. HTTP doesn't have a specification that allows a single request to serve multiple files without assistance from the browser (e.g. when resource X explicitly loads resource Y), and even if there were, Visualforce doesn't allow us to use arbitrary headers that we would need to support this logic. This leaves you with a couple of choices: 1) you could email the files to the recipient, 2) you could try to emit a ZIP file, or 3) you could try to concatenate the files into a ZIP file and provide a link to that resource. If email is a viable choice, you can use the interface provided by Apex Code for this. As for the others, they are non-trivial tasks, and I would probably skip trying them at all.

Answer 2

It will work if you want download selected document

function downloadFile() {
        var arrayOfLinks =[]
        j$('#downloadSelected .num ').each(function(i,val){
            var checkbox_cell_is_checked = j$(this).closest('tr').find('input').is(':checked');
            if(checkbox_cell_is_checked){
                arrayOfLinks.push(j$(this).text());
             }
        });
downloadAll(arrayOfLinks);
 }
function downloadAll(files){
        //alert('Inside'+files.length);
        if(files.length>0){
            var file = files.pop();
            //alert('Inside'+files.length);
            window.open(file, 'Download');
            setTimeout(downloadAll, 1500, files);
 }
}