题目：
将DOM节点元素转换成JSON的格式
例如

<div class="root">
     <div class="child1"><p></p></div>
    <span></span>
     <div><div><p></p></div></div>
    <p></p>
</div>

转换显示成(简写，大致表达个意思)：
{"tagName":"DIV", className="root", childs:[{"tagName":"DIV", className="root",childs:[]}]}

乍一看上去并不是很难，递归，找出各个节点的child节点即可，可真正当场写出代码还是需要锻炼锻炼，反正我当时没写出来，课后补习：
试一试：​​​http://jsrun.net/VPaKp/edit​​ HTML File:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=, initial-scale=">
    <meta http-equiv="X-UA-Compatible" content="">
    <title></title>
</head>
<body>
    <div class="root">
        <div class="child1"><p></p></div>
        <span class="span1"><span></span></span>
        <div><div><p class="p1"></p></div></div>
        <p><span></span></p>
    </div>
</body>
</html>

JS File:

function convertToJson() {
    const root = document.getElementsByClassName('root')[0];
    const output = new Object();
    output.tagName = root.tagName;
    output.className = root.className;
    output.childs = getChilds(root);

    console.log(JSON.stringify(output));
}

function getChilds(node) {
    const childs = node.children;
    const result = new Array();
    if(!childs || childs.length === 0) return result;
    for (const child of childs) {
        const childOutput = new Object();
        childOutput.tagName = child.tagName;
        childOutput.className = child.className;
        childOutput.childs = getChilds(child);
        result.push(childOutput);
    }
    return result;
}
convertToJson();

运行结果：
{"tagName":"DIV","className":"root","childs":[{"tagName":"DIV","className":"child1","childs":[{"tagName":"P","className":"","childs":[]}]},{"tagName":"SPAN","className":"span1","childs":[{"tagName":"SPAN","className":"","childs":[]}]},{"tagName":"DIV","className":"","childs":[{"tagName":"DIV","className":"","childs":[{"tagName":"P","className":"p1","childs":[]}]}]},{"tagName":"P","className":"","childs":[{"tagName":"SPAN","className":"","childs":[]}]}]}

随便找了一个格式化的网站把json字符串格式化显示下：




算法二：DOM - 将DOM节点元素转换成JSON字符串_elementui


在对比下HTML文件目录：

<div class="root">
        <div class="child1"><p></p></div>
        <span class="span1"><span></span></span>
        <div><div><p class="p1"></p></div></div>
        <p><span></span></p>
    </div>

就是这么回事。目前就是想到这个方法了，至于是不是最优就不得而知啦~