我有一组具有相同类名但没有独立id的div。它们在html中显示的顺序很重要，必须保留。我需要能够循环遍历由`document.getElementsByClassName(className);`给出的元素列表，并为它们每个提供一个形式为`"tile-1" "tile-2"`等的唯一id。
我认为像这样的代码可能有效，但很快我意识到这不会起作用：
```js 
const getTiles = document.getElementsByClassName(tileClass);
let n = 1;
for (e in getTiles){
  let i = "tile-" + n;  
  e.setAttribute("id", i);
  n++;
}

<details>
<summary>英文:</summary>
I have a set of divs that share a class name, but have no individual id. The order in which they show up in html is important and must be preserved. I need to be able to loop through the list of elements given by `document.getElementsByClassName(className);` and give them each a unique id in the form `&quot;tile-1&quot; &quot;tile-2&quot; etc`.
I thought something like this may work but I soon came to realise that this would not work:
```js 
const getTiles = document.getElementsByClassName(tileClass);
  let n = 1;
  for (e in getTiles){
    let i = &quot;tile-&quot; + n;  
    e.setAttribute(&quot;id&quot;, i);
    n++;
}

let i = 1;
document.querySelectorAll('.post').forEach(el => {
  el.id = 'title-' + i;
  i++
})

<div class="post">
</div>
<div class="post">
</div>
<div class="post">
</div>
<div class="post">
</div>