Tag Archives: snippet

jQuery: Get the Selected Option Text

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What’s the Task?

First of all let me explain what is the task. If there’s a select menu with several options, each of which are with a given value attribute, the task is to get the text into the option tag, and not that of the value attribute.

In that scenario let’s assume that we have the following HTML:

<select id="my-select">
    <option value="1">value 1</option>
    <option value="2">value 2</option>
</select>

select menu
Note that in the official jQuery doc page, the selector is described in the same context, but with a different markup:

<select id="my-select">
    <option>value 1</option>
    <option>value 2</option>
</select>

than the jQuery snippet looks like that:

$(document).ready(function() {
    $("#my-select").change(function() {
        alert($(this).val());
    });
});

Here’s interesting to note that there’s no value attribute set to the options, thus the selection of an element is correct and the returned value is correct. The problem is that this code doesn’t work correctly once you’ve a different value attribute, from the value enclosed into the option tag. In our case we’ve the markup shown on the first code snippet and we’d like to get the “value 2” string instead of “2”.

Source Code

<select id="my-select">
    <option value="1">value 1</option>
    <option value="2">value 2</option>
</select>
$(document).ready(function() {
    $("#my-select").change(function() {
        alert($(this).val());
    });
});

Solution

Finally the solution, is pretty simple and clear, but this time is not to so “native” and it’s definitely something you couldn’t expect! The only thing you’ve to do is to change the selector!

$(document).ready(function() {
    $("#my-select).change(function() {
        alert($('#my-select option:selected').html());
    });
});

Build a List Tree with the Beauty of jQuery

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This is nothing useful, but let me show the beauty of jQuery. This snippet just adds more and more nodes on a simple UL based tree.

Here’s the HTML:

<ul>
    <li><a href="#">Node 1</a></li>
    <li><a href="#">Node 2</a></li>
    <li><a href="#">Node 3</a></li>
    <li><a href="#">Node 4</a></li>
</ul>

And that’s the jQuery:

var index = 5;
$('li > a').live('click', function() {
    $(this).parent().append('<ul><li><a href="#">Node ' + index + '</a></li></ul>');
 
    index++;
 
    return false;
});

And here’s the demo.

JavaScript Comparision Snippet

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== vs. ===

I know this is really for beginners, but have you ever asked yourself what are the differences between == and === when comparing in JavaScript, and when to use it? Here’s an example:

var a = false;
alert(a === 0); // prints false

That’s false. Even when both the zero and the variable are faulty the entire operation is false. Because the 0 is a number and the variable a is boolean, therefore their different types give us the answer. If there was a comparision only with == the result would be true:

var a = false;
alert(a == 0); // prints true

It’s good when you expect some variable to match certain type to compare with ===. So the correct code is:

var a = false;
alert(a === false); // prints true

Here the type of a compares with boolean. See the complete demo.