I just use a bit of jQuery/javascript:
html:
<h1>Don't Print</h1>
<a data-target="#myModal" role="button" class="btn" data-toggle="modal">Launch modal</a>
<div class="modal fade hide" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3 id="myModalLabel">Modal to print</h3>
</div>
<div class="modal-body">
<p>Print Me</p>
</div>
<div class="modal-footer">
<button class="btn" data-dismiss="modal" aria-hidden="true">Close</button>
<button class="btn btn-primary" id="printButton">Print</button>
</div>
</div>
js:
$('#printButton').on('click', function () {
if ($('.modal').is(':visible')) {
var modalId = $(event.target).closest('.modal').attr('id');
$('body').css('visibility', 'hidden');
$("#" + modalId).css('visibility', 'visible');
$('#' + modalId).removeClass('modal');
window.print();
$('body').css('visibility', 'visible');
$('#' + modalId).addClass('modal');
} else {
window.print();
}
});
here is the fiddle