javascript - Defining an element in jQuery selector as optional? - Stack Overflow

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I'm trying to select an element through jQuery, but one of the element in the selection is optional. So I have something like this:

$('div.myClass span a>img')

In my scenario, that a element is an optional one. It may or may not exist in the DOM.

Of course, I can write out the entire line again with one containing a but this looks verbose:

$('div.myClass span a>img').css('opacity', 0.5);
$('div.myClass span img').css('opacity', 0.5);

Is it possible to define the a element to be optional in the jQuery selector path?

I'm trying to select an element through jQuery, but one of the element in the selection is optional. So I have something like this:

$('div.myClass span a>img')

In my scenario, that a element is an optional one. It may or may not exist in the DOM.

Of course, I can write out the entire line again with one containing a but this looks verbose:

$('div.myClass span a>img').css('opacity', 0.5);
$('div.myClass span img').css('opacity', 0.5);

Is it possible to define the a element to be optional in the jQuery selector path?

• javascript
• jquery

Share Improve this question Follow asked Sep 2, 2016 at 7:48 CarvenCarven 15.7k3030 gold badges124124 silver badges185185 bronze badges 0

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5 Answers 5

Sorted by: Reset to default 5

You only need the a > if you want to specifically target only images within the anchor. Otherwise, div.myClass span img will target any image inside the span.... regardless of the presence of an anchor tag.

---

$('div.myClass span a > img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS TARGETED" /></a> 
        <img src="BUT THIS IMAGE IS NOT" />
    </span>
</div>

---

$('div.myClass span img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS TARGETED" /></a> 
        <img src="THIS IMAGE IS ALSO TARGETED" />
    </span>
</div>

---

$('div.myClass span img').not('a > img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS ** NOT ** TARGETED" /></a> 
        <img src="THIS IMAGE IS TARGETED" />
    </span>
</div>

You can't make an optional element selector (other than using * but that's not a great idea). Instead you could bine both the selectors in to a single jQuery object, like this:

$('div.myClass span a>img, div.myClass span img').css('opacity', 0.5);

Note however that if the second selector is valid for your scenario, then the > selector is redundant anyway.

You can use a context and make your selectors behind it like:

$('a > img, img', 'div.myClass span').css('opacity', 0.5);

And in your case, you only need the img because a > img will select the same image:

$('img', 'div.myClass span').css('opacity', 0.5);

Use only

$('div.myClass span img').css('opacity', 0.5);

It will work as your requirements.

You could also cut the expression, and use find

$('div.myClass span').find('a>img, img').css('opacity', 0.5);

I'm trying to select an element through jQuery, but one of the element in the selection is optional. So I have something like this:

$('div.myClass span a>img')

In my scenario, that a element is an optional one. It may or may not exist in the DOM.

Of course, I can write out the entire line again with one containing a but this looks verbose:

$('div.myClass span a>img').css('opacity', 0.5);
$('div.myClass span img').css('opacity', 0.5);

Is it possible to define the a element to be optional in the jQuery selector path?

I'm trying to select an element through jQuery, but one of the element in the selection is optional. So I have something like this:

$('div.myClass span a>img')

In my scenario, that a element is an optional one. It may or may not exist in the DOM.

Of course, I can write out the entire line again with one containing a but this looks verbose:

$('div.myClass span a>img').css('opacity', 0.5);
$('div.myClass span img').css('opacity', 0.5);

Is it possible to define the a element to be optional in the jQuery selector path?

• javascript
• jquery

Share Improve this question Follow asked Sep 2, 2016 at 7:48 CarvenCarven 15.7k3030 gold badges124124 silver badges185185 bronze badges 0

Add a ment  | 

5 Answers 5

Sorted by: Reset to default 5

You only need the a > if you want to specifically target only images within the anchor. Otherwise, div.myClass span img will target any image inside the span.... regardless of the presence of an anchor tag.

---

$('div.myClass span a > img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS TARGETED" /></a> 
        <img src="BUT THIS IMAGE IS NOT" />
    </span>
</div>

---

$('div.myClass span img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS TARGETED" /></a> 
        <img src="THIS IMAGE IS ALSO TARGETED" />
    </span>
</div>

---

$('div.myClass span img').not('a > img');

<div class="myClass">
    <span>
        <a href="#"><img src="THIS IMAGE IS ** NOT ** TARGETED" /></a> 
        <img src="THIS IMAGE IS TARGETED" />
    </span>
</div>

You can't make an optional element selector (other than using * but that's not a great idea). Instead you could bine both the selectors in to a single jQuery object, like this:

$('div.myClass span a>img, div.myClass span img').css('opacity', 0.5);

Note however that if the second selector is valid for your scenario, then the > selector is redundant anyway.

You can use a context and make your selectors behind it like:

$('a > img, img', 'div.myClass span').css('opacity', 0.5);

And in your case, you only need the img because a > img will select the same image:

$('img', 'div.myClass span').css('opacity', 0.5);

Use only

$('div.myClass span img').css('opacity', 0.5);

It will work as your requirements.

You could also cut the expression, and use find

$('div.myClass span').find('a>img, img').css('opacity', 0.5);

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