js IntersectionObserver简单案例

效果

源码

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<!DOCTYPE html>
<!DOCTYPE html>
<html lang="en">
	<head>
		<meta charset="UTF-8">
		<meta http-equiv="X-UA-Compatible" content="IE=edge">
		<meta name="viewport" content="width=device-width, initial-scale=1.0">
		<title>IntersectionObserver</title>
		<style>
			div {
				height: 700px;
			}
		</style>
	</head>
	<body>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>
		<div></div>

		<script>
			let observer = new IntersectionObserver((entries) => {
				entries.forEach(entry => {
					entry.target.innerText = entry.isIntersecting ? '测试' : '';
					entry.target.style["background-color"] = entry.isIntersecting ? 'red' : 'blue';
					entry.target.style["font-size"] = entry.isIntersecting ? '80px' : '';
				})
			}, {
				root: null, // 根元素，null为视口
				threshold: 0.5 //重叠率 0.0-1.0  重叠率达到要求后触发事件 
			});

			document.querySelectorAll('div').forEach(element => {
				observer.observe(element)
			});
		</script>
	</body>
</html>
javascript
#js #javascript #IntersectionObserver #dom懒加载
js IntersectionObserver简单案例
https://github.com/chergn/chergn.github.io/bd40c47a0c8d/
作者
全易
发布于
2024年3月28日
许可协议