How to pull values from dropdown using jQuery

How to pull values from dropdown using jQuery, like top 10, top20, top100, these values are defined in drop down, how to pull these values in a variable and update variable value dynamically based on drop down selection.

 

Since "a dropdown" isn't really a semantic container, it's hard to say how the jQuery should look, but if it is, for instance, a list, just do something like:

var listItem = $("#list_name li").text();

Code (markup):

or something similar

Or maybe post some code, so we know what we're dealing with...

 

Let me help you construct a bare HTML dropdown to start with;

<select id="countries">
    <option value="US">USA</option>
    <option value="UK">Britain</option>
    <option value="FR">France</option>
</select>

HTML:

And from that structure, you can use jQuery to get anything you want from the selected drop down;

//For the text
var txt = $('#countries').find('option:selected').text();

//For other attributes inside <option>
var v = $('#countries').find('option:selected').attr('value');

Code (markup):