Vue 图片预加载

setup() {
    const imgList = [
      "https://cdn.example.com/1.jpg",
      "https://cdn.example.com/2.jpg",
      "https://cdn.example.com/3.jpg",
      "https://cdn.example.com/4.jpg",
    ];

    //图片预加载
    const loadImg = (imgList) => {
      for (let i = 0; i < imgList.length; i++) {
        let img = new Image()
        let currentSrc = ''
        img.src = imgList[i]
        img.onload = function (e) {
          //二次缓存，主要针对带中文的图片链接
          if (currentSrc.length === 0) {
            currentSrc = this.currentSrc
            img.src = currentSrc
            console.log('二次缓存');
          }
          console.log('加载完毕', e, this.currentSrc);
        }
        img.onerror = function (e) {
          console.log('加载错误', e);
        }
      }
    }

    onMounted(() => {
    	loadImg(imgList);
    })

    return {
      loadImg,
      imgList,
      onMounted
    };
},