how to append a <option> value to dropdown using jquery - php

Question

I am working on a project in which i have to append a dropdown options to selection list .I have tried to append options but am not getting them in dropdown. while i am getting values in debugging
$("#p_combination").empty();
for(var i = 0; i < len; i++) {
var dish_name = response[i]['dish_name'];
var pincode = response[i]['pincode'];
$("#p_combination").append("<option value='" + dish_name + "'>" + dish_name + "</option>");
document.getElementById('pincode').value = pincode;
}
<select name="p_combination[]" id="p_combination" multiple>
<option value="0">Select</option>
</select>

Answer 1

Try this:
$("#p_combination").empty();
//supposing that your response object is something like :
var response=[{'dish_name':'name1','pincode':1},{'dish_name':'name2','pincode':2},{'dish_name':'name3','pincode':3}];
for(var i = 0; i < response.length; i++) {
$("#p_combination").append("<option value='" + response[i]['dish_name'] + "'>" +response[i]['dish_name'] + "</option>");
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<select name="p_combination[]" id="p_combination" multiple>
<option value="0">Select</option>
</select>

Answer 2

You can use the .append() method in jQuery as in the following example.
Working Example:
$(document).ready(function(){
$('button').click(function(){
var newOptionValue = $('option').length;
$('select').append('<option value="' + newOptionValue + '">Option ' + newOptionValue + '</option>');
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select name="p_combination[]" id="p_combination" multiple>
<option value="0">Option 0</option>
</select>
<button type="button">Append Option</button>