bootstrap 4 open modal on button click code example

Example 1: open bootstrap modal using javascript

$("#myModal").modal(); //open modal
$('#myModal').modal('toggle'); //open modal
$('#myModal').modal('show'); //open modal
$('#myModal').modal('hide'); //hide modal
//@sujay

Example 2: bootstrap 4 start modal in modal

var modal_lv = 0;
$('.modal').on('shown.bs.modal', function (e) {
    $('.modal-backdrop:last').css('zIndex',1051+modal_lv);
    $(e.currentTarget).css('zIndex',1052+modal_lv);
    modal_lv++
});

$('.modal').on('hidden.bs.modal', function (e) {
    modal_lv--
});