html2canvas将document DOM节点转换为图片，并下载到本地

npm install --save html2canvas

<template>
    <div>
        <el-button type="primary" ref="btn" @click="downloadImg({ dom: $el, fileName: '自定义图片名称.png' })">下载当前网页</el-button>
    </div>
</template>
<script>
import html2canvas from 'html2canvas'; // npm install --save html2canvas (官网：https://html2canvas.hertzen.com)
export default {
    methods: {
        downloadImg({ dom, fileName = '', fileType = 'image/png', quality = 1.0 } = {}) {
            html2canvas(dom, { width: dom.scrollWidth, height: dom.scrollHeight, }).then(canvas => { let a = document.createElement('a'); a.download = fileName, a.href = canvas.toDataURL(fileType, quality), a.click(); });
        },
    }
};
</script>