How to download a file from the view on button click?

Question

I need to add a button in my view file which allows a user to download a file from the front end of the website. Everything is working fine re: displaying data however I'm not sure how to offer up a downloadable file based on data in a variable.

Here is the data which is being generated from the view file.

<?php
$vCardData[$i] = '
BEGIN:VCARD
VERSION:4.0
N:'.${'data'.$i}['l_name'].';'.${'data'.$i}['f_name'].';;;
FN:'.${'data'.$i}['title'].' '.${'data'.$i}['f_name'].' '.${'data'.$i}['l_name'].'
ORG:'.${'data'.$i}['company'].'
TEL;TYPE=work,voice;VALUE=uri:tel:'.${'data'.$i}['company_contact_number'].'
TEL;TYPE=home,voice;VALUE=uri:tel:'.${'data'.$i}['number'].'
ADR;TYPE=work;LABEL="'.${'data'.$i}['address_1'].' '.${'data'.$i}['address_2'].'\n'.${'data'.$i}['city'].', '.${'data'.$i}['county'].' '.${'data'.$i}['post_code'].'\n'.${'data'.$i}['county'].'"
:;;'.${'data'.$i}['address_1'].' '.${'data'.$i}['address_2'].';'.${'data'.$i}['city'].';'.${'data'.$i}['county'].';'.${'data'.$i}['post_code'].';'.${'data'.$i}['county'].'
EMAIL:'.${'data'.$i}['email'].'
REV:'.time().'
END:VCARD
';
?>

I need to somehow use the CodeIgniter force_download() on click of an anchor from within the view file. I have tried adding <?php echo site_url( 'controller/function' ); ?> <?php echo site_url( 'controller/function' ); ?> to the anchor tag however this is just directing me to a page on the site http://example.com/controller/function and I'm assuming that's because it's called from the front end.

Is there any way to achieve this?

Further notes: My controller is selecting all the data from the database and passing it to my address_book view. In the address_book view I have the following:

<?php for ($i = 0; $i < $count; $i++) { ?>
    <div class="col-sm-6 contact_card">
        <h4><?php echo ${'data'.$i}['title']; echo ${'data'.$i}['f_name']; echo ${'data'.$i}['l_name']; ?></h4>
        <?php if (${'data'.$i}['email']) { echo 'e: <a href="mailto:'.${'data'.$i}['email'].'">'.${'data'.$i}['email'].'</a>'; }
        if (${'data'.$i}['number']) { echo '<p>t: '.${'data'.$i}['number'].'</p>'; }

        $vCardData[$i] = '
        BEGIN:VCARD
        VERSION:4.0
        N:'.${'data'.$i}['l_name'].';'.${'data'.$i}['f_name'].';;;
        FN:'.${'data'.$i}['title'].' '.${'data'.$i}['f_name'].' '.${'data'.$i}['l_name'].'
        ORG:'.${'data'.$i}['company'].'
        TEL;TYPE=work,voice;VALUE=uri:tel:'.${'data'.$i}['company_contact_number'].'
        TEL;TYPE=home,voice;VALUE=uri:tel:'.${'data'.$i}['number'].'
        ADR;TYPE=work;LABEL="'.${'data'.$i}['address_1'].' '.${'data'.$i}['address_2'].'\n'.${'data'.$i}['city'].', '.${'data'.$i}['county'].' '.${'data'.$i}['post_code'].'\n'.${'data'.$i}['county'].'"
        :;;'.${'data'.$i}['address_1'].' '.${'data'.$i}['address_2'].';'.${'data'.$i}['city'].';'.${'data'.$i}['county'].';'.${'data'.$i}['post_code'].';'.${'data'.$i}['county'].'
        EMAIL:'.${'data'.$i}['email'].'
        REV:'.time().'
        END:VCARD
        ';?>

        <a href="<?php echo site_url('address_book/vcard') ?>">Download vCard</a>

    </div>
<?php }

Answer 1

Have you considered handling this at the server level rather than in the application? Your webserver could/should be configured to return .vcf as attachments. Related: stackoverflow.com/questions/5116772/…

Perhaps EE overwrites those headers tho? If so here's a free EE extension that allows you to extend template types (each of which can have their own mime type):

http://devot-ee.com/add-ons/template-image-mime-type

You could easily modify this extension to include the download handling you require.

I think you want: application/octet-stream for .vcf