Calling a function on Bootstrap modal open

You can use the shown event/show event based on what you need:

$( "#code" ).on('shown', function(){
    alert("I want this to appear after the modal has opened!");
});

Demo: Plunker

Update for Bootstrap 3.0

For Bootstrap 3.0 you can still use the shown event but you would use it like this:

$('#code').on('shown.bs.modal', function (e) {
  // do something...
})

See the Bootstrap 3.0 docs here under “Events”.