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HTML

              
                <!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <title>Document</title>
        <style>
            img {
                width: 100%;
                height: 300px;
            }
        </style>
    </head>
    <body>
        <div id="app">
            <p v-for="item in imgs" :key="item">
                <img v-lazyload="item">
            </p>
        </div>
    </body>
    <script src="https://cdn.jsdelivr.net/npm/vue"></script>
    <script>
        Vue.directive("lazyload", {
            // 指令的定义
            bind: function(el, binding) {
                let lazyImageObserver = new IntersectionObserver((entries, observer) => {
                    entries.forEach((entry, index) => {
                        let lazyImage = entry.target;
                        // 相交率,默认是相对于浏览器视窗
                        if(entry.intersectionRatio > 0) {
                            lazyImage.src = binding.value;
                            // 当前图片加载完之后需要去掉监听
                            lazyImageObserver.unobserve(lazyImage);
                        }

                    })
                })
                lazyImageObserver.observe(el);
            },
        });
        var app = new Vue({
            el: "#app",
            data: {
                imgs: [
                    'https://ss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=1825933799,1197547007&fm=26&gp=0.jpg',
                    'https://ss1.bdstatic.com/70cFvXSh_Q1YnxGkpoWK1HF6hhy/it/u=2731360590,3226816949&fm=26&gp=0.jpg',
                    'https://ss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=1825933799,1197547007&fm=26&gp=0.jpg',
                    'https://ss1.bdstatic.com/70cFvXSh_Q1YnxGkpoWK1HF6hhy/it/u=2731360590,3226816949&fm=26&gp=0.jpg',
                    'https://ss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=1825933799,1197547007&fm=26&gp=0.jpg',
                    'https://ss1.bdstatic.com/70cFvXSh_Q1YnxGkpoWK1HF6hhy/it/u=2731360590,3226816949&fm=26&gp=0.jpg',
                    'https://ss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=1825933799,1197547007&fm=26&gp=0.jpg',
                    'https://ss1.bdstatic.com/70cFvXSh_Q1YnxGkpoWK1HF6hhy/it/u=2731360590,3226816949&fm=26&gp=0.jpg',
                ]
            },
        });
    </script>
</html>
              
            
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