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I want to use hasClass in the following code, but that doesn't work for me, please see my demo in jsfiddle and tell me, what do I do wrong?

<span>
    <input type="text" name="relation" class="IdRelation">
</span>
​

if ($('span').hasClass('IdRelation')) {
  alert("ok");
}​

DEMO

I want to use hasClass in the following code, but that doesn't work for me, please see my demo in jsfiddle and tell me, what do I do wrong?

<span>
    <input type="text" name="relation" class="IdRelation">
</span>
​

if ($('span').hasClass('IdRelation')) {
  alert("ok");
}​

DEMO

• javascript
• jquery

Share Improve this question Follow edited Jul 26, 2012 at 12:27 mplungjan 179k2828 gold badges182182 silver badges240240 bronze badges asked Jul 26, 2012 at 12:23 jennifer Joliejennifer Jolie 72766 gold badges1717 silver badges3131 bronze badges 3

• 2 It kind of looks like you're using IdRelation as a unique marker (obviously just a guess based on your markup). If so you might want to consider using id="relation" instead and select it using $("#relation"). – Vala Commented Jul 26, 2012 at 12:29
• 1 Especially with the prefix Id which does not sound like it would be a class – mplungjan Commented Jul 26, 2012 at 12:36
• 1 there is no span with a class IdRelation, did you mean input? – jbabey Commented Jul 26, 2012 at 12:39

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2 Answers 2

Sorted by: Reset to default 11

It is not the <span> element that exposes the IdRelation class, but its <input> child. Try:

if ($("span input").hasClass("IdRelation")) {
    alert("ok");
}​

Or maybe, depending on your actual markup:

if ($("span > input").hasClass("IdRelation")) {
    alert("ok");
}​

The selector in the first code snippet will match all <input> elements that are descendants of a <span> element, whereas the selector in the second snippet will match all <input> elements that are direct children of a <span> element. Both will match the <input> element in your sample markup.

Solution

The class is on the <span> child, an <input>, so add it in the jQuery selector : $('span input').

if ($('span input').hasClass('IdRelation')) {
  alert('ok');
}​

Try the Demo.

A bit of explanation

Accorting to jQuery documentation, $('span input') is a descendant selector :

Selects all elements that are descendants of a given ancestor.

You could also use $('span > input'). It is a child selector :

Selects all direct child elements specified by "child" of elements specified by "parent".

Both are good in your situation, because the input is a direct child of the <span>.

If your code was :

<div>
    <form>
        <input type="text" name="relation" class="IdRelation">
    </form>
</div>

The solution will be $('div input') or $('div > form > input').

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