Passing variables?! Halp!

I’ve created a function to generate “buttons” on the site, but the following doesn’t appear to work:

<?php $thetitle=the_title(); ?>
<?php echo button($type,$link,$icon,$thetitle); ?>

When I do this, the title for the button ends up blank. If I manually insert text, the text appears (so I know the function works)

How do I pass WP variables like the_title(), the_permalink(), the_date() etcetera?

Hope you can help!