How do you check if an element is a child in javascript?
Summary: in this tutorial, you will learn how to get the first child element, last child element, and all children of a specified element. Show Suppose that you have the following HTML fragment:
Get the first child elementTo get the first child element of a specified element, you use the
If the
Output:
The Console window show Note that any whitespace such as a single space, multiple
spaces, returns, and tabs will create a
Or to get the first child with the Element node only, you can use the
The following code returns the first list item which is the first child element of the menu:
Output:
In this example:
Get the last child elementTo get the last child element of a node, you use the
In case the
The following code returns the list item which is the last child element of the menu:
Output:
To get a live
The
The following example selects all child elements of the element with the Id
Output: Summary
Was this tutorial helpful ? How do you check if an element has a child in JS?Use the querySelector() method to check if an element has a child with a specific id, e.g. if (box. querySelector('#child-3') !== null) {} . The querySelector method returns the first element that matches the provided selector or null of no element matches.
How do you check if an element has a child?To check if an HTML element has child nodes, you can use the hasChildNodes() method. This method returns true if the specified node has any child nodes, otherwise false . Whitespace and comments inside a node are also considered as text and comment nodes.
How do you get a child in JavaScript?To get the first child element of a specified element, you use the firstChild property of the element:. let firstChild = parentElement.firstChild; ... . let content = document.getElementById('menu'); let firstChild = content.firstChild.nodeName; console.log(firstChild); ... . #text.. How do you check if a DOM element is a child of another?Check if an element is a descendant of another. Use the contains method. const isDescendant = parent. contains(child);. Go up from the child until see the parent. // Check if `child` is a descendant of `parent` const isDescendant = function (parent, child) { let node = child. parentNode; while (node) {. |