I have problem regarding getting the value in input textbox, this textbox was in modal form. I'm confuse when i put static value in input textbox the value is not empty, however when i use the element id value i can't get any value and the alert shows empty.
Modal:
<form action="" method="post" enctype="multipart/form-data">
<div class="modal fade" id="exampleModalCenter" tabindex="-1" role="dialog" aria-labelledby="exampleModalCenterTitle" aria-hidden="true">
<div class="modal-dialog modal-dialog-centered" role="document">
<div class="modal-content">
<div class="modal-header">
<h5 class="modal-title" id="exampleModalLongTitle">New Menu Section</h5>
<button type="button" class="close" data-dismiss="modal" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
</div>
<div class="modal-body">
<div class="row">
<div class="col-md-6">
<label>Menu Name</label>
<input placeholder="For sharing..." name="menu_name_category" value="" class="form-control" id="menu_value" type="text" class="validate">
</div>
</div>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
<button type="button" class="btn btn-primary" id="save_menu_button">Save changes</button>
</div>
</div>
</div>
</div>
</form>
Javascript & Jquery:
var textFieldVal = document.getElementById("menu_value").value;
$('#save_menu_button').click(function() {
alert(textFieldVal);
});