> For the complete documentation index, see [llms.txt](https://quantumphp.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quantumphp.gitbook.io/docs/packages/cookie/overview.md).

# Overview

Cookie provides a small encrypted wrapper around PHP cookies.

Use it when you want to read and write cookie values through Quantum instead of working with raw `$_COOKIE` and `setcookie(...)` calls.

## What it provides

* `Quantum\Cookie\Cookie` storage wrapper
* `cookie()` helper as the standard entry point
* automatic encryption on write and decryption on read

## Quick example

```php
cookie()->set('theme', 'dark', 3600, '/', '', true, true);

if (cookie()->has('theme')) {
    $theme = cookie()->get('theme');
}

cookie()->delete('theme');
```

## Operational constraints

* values are encrypted before they are written and decrypted when they are read
* `set()` stores the value in the current request storage immediately and also sends a `Set-Cookie` header
* `time` is treated as seconds from now; `0` creates a session cookie
* `has()` treats empty values as missing, so `''`, `0`, `'0'`, `false`, and `null` do not count as present
* `get()` depends on `has()`, so those values come back as `null`


---

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