javascript - querySelectorAll 返回什么类型的数据？

Question

这个问题已经有答案了:

What do querySelectorAll and getElementsBy* methods return? (12 个回答)

已关闭 2 年前。

javaScript 对象没有 length 属性，但返回值 querySelectorAll有一个 length 属性，表明它是一个数组。但如果我们通过 Array.isArray() 检查它然后返回 false，证明它不是数组。那么它是什么类型的数据呢？

var obj1 = {
  fname: "Mirajul",
  lname: "Momin",
  age: 24
};
console.log(obj1.length);
var paraList = document.querySelectorAll("p");
console.log(paraList.length);
console.log(Array.isArray(paraList));

<p>This is paragraph one</p>
<p>This is paragraph two</p>
<p>This is paragraph three</p>
<p>This is paragraph four</p>

Answer 1

The Element method querySelectorAll() returns a static (not live) NodeList representing a list of the document's elements that match the specified group of selectors.

有关差异，请访问:Difference between HTMLCollection, NodeLists, and arrays of objects

您可以使用Spread syntax将其作为数组:

var obj1 = {
  fname: "Mirajul",
  lname: "Momin",
  age: 24
};
console.log(obj1.length);
var paraList = [...document.querySelectorAll("p")];
console.log(paraList.length);
console.log(Array.isArray(paraList));

<p>This is paragraph one</p>
<p>This is paragraph two</p>
<p>This is paragraph three</p>
<p>This is paragraph four</p>