> For the complete documentation index, see [llms.txt](https://lochiwei.gitbook.io/web/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://lochiwei.gitbook.io/web/js/val/builtin/arr/access.md).

# accessing elements

[JS](/web/js.md) ⟩ [object](/web/js/val/obj.md) ⟩ [built-in](/web/js/val/builtin.md) ⟩ [Array](/web/js/val/builtin/arr.md) ⟩ accessing arrays

{% hint style="success" %}

```javascript
arr.push(value)    // append element
arr.pop()          // removes and returns last element
arr.unshift(value) // prepend element
arr.shift()        // removes and returns first element

delete a[1]        // delete element

//                             ┌────────┐ <--- elements to add
arr.splice(index, deleteCount, v1, v2, v3)
//           └── start index to delete/insert elements
```

{% endhint %}

{% tabs %}
{% tab title="⭐️ 重點" %}
{% hint style="info" %}
**array** [**elements**](/web/js/val/builtin/arr/element.md) can be <mark style="color:yellow;">**deleted**</mark> with the [**delete**](/web/js/val/obj/prop/create/delete.md) operator.
{% endhint %}
{% endtab %}

{% tab title="🔴 主題" %}

* [element index](/web/js/val/builtin/arr/element/index.md)
* [element](/web/js/val/builtin/arr/element.md)
* [array object property](/web/js/val/builtin/arr/obj-prop.md)
  {% endtab %}

{% tab title="👥 相關" %}

* :white\_check\_mark: [element](/web/js/val/builtin/arr/element.md)(s) are <mark style="color:yellow;">**accessed**</mark> throught [element index](/web/js/val/builtin/arr/element/index.md) using [bracket notation \[\]](/web/js/val/obj/prop/access/bracket-notation.md).
* an [Array](/web/js/val/builtin/arr.md) may have its own [array object property](/web/js/val/builtin/arr/obj-prop.md)(s):exclamation:
  {% endtab %}

{% tab title="📗 參考" %}

* [ ] JS.info ⟩ [iterables](https://javascript.info/iterable)
* [ ] [JavaScript: The Definitive Guide](/web/master/ref/javascript-the-definitive-guide.md) ⟩ 7.5 Adding and Deleting Array Elements
  {% endtab %}

{% tab title="📘 手冊" %}

* [Array.prototype.splice()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice) - insert/delete elements.
  {% endtab %}
  {% endtabs %}