How to check whether a select box is empty using JQuery/Javascript

One correct way to get selected value would be

var selected_value = $('#fruit_name').val()

And then you should do

if(selected_value) { ... }

To check whether select box has any values:

if( $('#fruit_name').has('option').length > 0 ) {

To check whether selected value is empty:

if( !$('#fruit_name').val() ) {