How do I get the n-th level parent of an element i

问题:

When I want to get, for example, the 3rd level parent of the element I must write $('#element').parent().parent().parent() Is there a more optimal method for this?

回答1:

Since parents() returns the ancestor elements ordered from the closest to the outer ones, you can chain it into eq():

$('#element').parents().eq(0);  // "Father".
$('#element').parents().eq(2);  // "Great-grandfather".

回答2:

Depends on your needs, if you know what parent your looking for you can use the .parents() selector.

E.G: http://jsfiddle.net/HenryGarle/Kyp5g/2/

<div id="One">
    <div id="Two">
        <div id="Three">
            <div id="Four">

            </div>
        </div>
    </div>
</div>


var top = $("#Four").parents("#One");

alert($(top).html());

Example using index:

//First parent - 2 levels up from #Four
// I.e Selects div#One
var topTwo = $("#Four").parents().eq(2);

alert($(topTwo ).html());

回答3:

You could give the target parent an id or class (e.g. myParent) and reference is with $('#element').parents(".myParent")

回答4:

A faster way is to use javascript directly, eg.

var parent = $(innerdiv.get(0).parentNode.parentNode.parentNode);

This runs significantly faster on my browser than chaining jQuery .parent() calls.

See: http://jsperf.com/jquery-get-3rd-level-parent

回答5:

If you have a common parent div you can use parentsUntil() link

eg: $('#element').parentsUntil('.commonClass')

Advantage is that you need not to remember how many generation are there between this element and the common parent(defined by commonclass).

回答6:

It's simple. Just use

$(selector).parents().eq(0); 

where 0 is the parent level (0 is parent, 1 is parent's parent etc)

回答7:

If you plan on reusing this functionality, the optimal solution is to make a jQuery plugin:

(function($){
$.fn.nthParent = function(n){
  var $p = $(this);
  while ( n-- >= 0 )
  {
    $p = $p.parent();
  }
  return $p;
};
}(jQuery));

Of course, you may want to extend it to allow for an optional selector and other such things.

One note: this uses a 0 based index for parents, so nthParent(0) is the same as calling parent(). If you'd rather have 1 based indexing, use n-- > 0

回答8:

Just add :eq() selector like this:

$("#element").parents(":eq(2)")

You just specify index which parent: 0 for immediate parent, 1 for grand-parent, ...

回答9:

you can also use :

$(this).ancestors().eq(n) 

ex: $(this).ancestors().eq(2) -> the parent of the parent of this.

回答10:

Didn't find any answer using closest() and I think it's the most simple answer when you don't know how many levels up the required element is, so posting an answer:
You can use the closest() function combined with selectors to get the first element that matches when traversing upwards from the element:

('#element').closest('div')    // returns the innermost 'div' in its parents
('#element').closest('.container')    // returns innermost element with 'container' class among parents
('#element').closest('#foo')    // returns the closest parent with id 'foo'

回答11:

You could use something like this:

(function($) {
    $.fn.parentNth = function(n) {
        var el = $(this);
        for(var i = 0; i < n; i++)
            el = el.parent();

        return el;
    };
})(jQuery);

alert($("#foo").parentNth(2).attr("id"));

http://jsfiddle.net/Xeon06/AsNUu/

回答12:

using eq appears to grab the dynamic DOM whereas using .parent().parent() appears to grab the DOM that was initially loaded (if that is even possible).

I use them both on an element that has classes applied it to on onmouseover. eq shows the classes while .parent().parent() doesnt.

回答13:

As parents() returns a list, this also works

$('#element').parents()[3];