IntersectionObserverEntry.isIntersecting

The IntersectionObserverEntry interface's read-only isIntersecting property is a Boolean value which is true if the target element intersects with the intersection observer's root. If this is true, then, the IntersectionObserverEntry describes a transition into a state of intersection; if it's false, then you know the transition is from intersecting to not-intersecting.

Syntax

var isIntersecting = IntersectionObserverEntry.isIntersecting;

Value

A Boolean value which indicates whether the target element has transitioned into a state of intersection (true) or out of a state of intersection (false).

Example

In this simple example, an intersection callback is used to update a counter of how many targeted elements are currently intersecting with the intersection root.

function intersectionCallback(entries) {
  entries.forEach(function(entry) {
    if (entry.isIntersecting) {
      intersectingCount += 1;
    } else {
      intersectingCount -= 1;
    }
  });
}

To see a more concrete example, take a look at Handling intersection changes in Timing element visibility with the Intersection Observer API.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
isIntersecting
51
16
55
No
Yes
12.1
51
51
55
?
12.2
5.0

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https://developer.mozilla.org/en-US/docs/Web/API/IntersectionObserverEntry/isIntersecting