Answers for "php function to display bootstrap 4 modal popup"

bootstrap 4 modal popup remote url

$('body').on('click', '[data-toggle="modal"]', function(){
        $($(this).data("target")+' .modal-body').load($(this).data("remote"));
    });

bootstrap modal show event

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