Could not set the select option value using jquery and PHP - php

Question

I have an issue. I need to set the select value as text in the select box using jQuery but unable to do it.
<select name="countryCode" class="chosen-select" id="countryCode" required>
<?php foreach ($countrydata as $key => $value) {
if ($value['con_code']=='IN') {
$select='selected';
}else{
$select='';
}
?>
<option data-text="<?php echo $value['country']; ?>" value="<?php echo $value['dial_code']; ?>" <?php echo $select; ?>><?php echo $value['country']; ?></option>
<?php } ?>
</select>
My script part is given below.
$('#countryCode').find(':selected').html($('#countryCode').find(':selected').attr('value')); // already changed onload
$('#countryCode').on('change mouseleave', function () {
$('#countryCode option').each(function () {
$(this).html($(this).attr('data-text'));
});
$('#countryCode option:selected').html($('#countryCode option:selected').attr('value'));
$(this).blur();
});
$('#countryCode').on('focus', function () {
$('#countryCode option').each(function () {
$(this).html($(this).attr('data-text'));
});
});
What I need is that when the user selects any text, it's value will be shown to the user. In my code it's not happening like this.

Answer 1

1st: a little optimization of your JS :
$('#countryCode option:selected').html($(this).val());// already changed onload
Now, how to select an option using JS :
$(function() {
var $sel = $('.chosen-select');
$('#exists').click(function() {
$sel.val('option3');
console.log($sel.val());
});
$('#disabled').click(function() {
$sel.val('option2');
console.log($sel.val());
});
$('#noExist').click(function() {
$sel.val('option5');
console.log($sel.val());
});
$sel.on('change', function() {
console.log($sel.val());
});
});
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<button id="exists">Select 3rd option</button>
<button id="disabled">Select disabled option</button>
<button id="noExist">Select inexistant option</button>
<select class="chosen-select">
<option>option1</option>
<option disabled>option2</option>
<option>option3</option>
<option selected>option4</option>
</select>
<button onclick="console.clear();">X</button>
As you can see, only existant and not disabled options can be selected.

Answer 2

should be something like this:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
$(function(){
$('#countryCode').on('change', function(){
var val = $(this).val();
$(this).find("option").each(function(){
$(this).text($(this).attr("data-text"));
});
$(this).find(":selected").text(val);
}).trigger("change");
});
</script>
<select id="countryCode" class="chosen-select">
<option data-text="A Text" value="A value">A Text</option>
<option data-text="B Text" value="B value">B Text</option>
<option data-text="C Text" value="C value" selected>C Text</option>
</select>