[javascript] How to select a single child element using jQuery?

Using jQuery how do I select a single child element? I've looked at the Traversing API and know I can select all the immediate children img elements like this:

$(this).children('img');

And to select the first child img element I could use a subscript like this:

$(this).children('img')[0];

But I guess I'm kind of surprised I can't do this:

$(this).child('img'); // no subscript, returns single element

Or have I missed something?

This question is related to javascript jquery dom-traversal

The answer is


You can target the first child element with just using CSS selector with jQuery:

$(this).children('img:nth-child(1)');

If you want to target the second child element just change 1 to 2:

$(this).children('img:nth-child(2)');

and so on..

if you want to target more elements, you can use a for loop:

for (i = 1; i <= $(this).children().length; i++) {
    let childImg =  $(this).children("img:nth-child("+ i +")");
    // Do stuff...
}

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Not jQuery, as the question asks for, but natively (i.e., no libraries required) I think the better tool for the job is querySelector to get a single instance of a selector:

let el = document.querySelector('img');
console.log(el);

For all matching instances, use document.querySelectorAll(), or for those within another element you can chain as follows:

// Get some wrapper, with class="parentClassName"
let parentEl = document.querySelector('.parentClassName');
// Get all img tags within the parent element by parentEl variable
let childrenEls = parentEl.querySelectorAll('img');

Note the above is equivalent to:

let childrenEls = document.querySelector('.parentClassName').querySelectorAll('img');

I think what you want to do is this:

$(this).children('img').eq(0);

this will give you a jquery object containing the first img element, whereas

$(this).children('img')[0];

will give you the img element itself.


Maybe in this way?

$('img', this)[0]