---
title: Attributes.set()
---

The `Attributes.set()` method sets the attribute identified by `key` to value
`value`.

## Signature

```js
Attributes attributes.set(string key, string value)
```

## Example

```js
const attr = new Attributes()
  .add('class', 'classA')
  .add('class', 'classB')

const class = attr.get('class')
// class now holds: "classA classB"
```

## Notes

This will overwrite any value that's currently set on the attribute identified
by `key`.