ES6是否为对象属性引入了明确定义的枚举顺序?
var o = {
'1': 1,
'a': 2,
'b': 3
}
Object.keys(o); // ["1", "a", "b"] - is this ordering guaranteed by ES6?
for(let k in o) {
console.log(k);
} // 1 2 3 - is this ordering guaranteed by ES6?
Run Code Online (Sandbox Code Playgroud) 有没有办法获取有序列表项的数字的内容?
var list = document.getElementById('list');
list.style.listStyleType = 'upper-roman';
Run Code Online (Sandbox Code Playgroud)
<ol class="list" id="list">
<li class="list__item">apple</li>
<li class="list__item">banana</li>
<li class="list__item" id="target">orange</li>
<li class="list__item">pear</li>
</ol>Run Code Online (Sandbox Code Playgroud)
这将产生这样的项目列表.
I. apple
II. banana
III. orange
IV. pear
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III的文本字符串#target?这里的罗马字符只是一个例子.我希望能够访问任何list-style-type选项提供的内容.