# Alnum

- `v::alnum()`
- `v::alnum(string $additionalChars)`

Validates alphanumeric characters from a-Z and 0-9.

```php
v::alnum()->validate('foo 123'); //true
```

A parameter for extra characters can be used:

```php
v::alnum('-')->validate('foo - 123'); //true
```

This validator allows whitespace, if you want to
remove them add `->noWhitespace()` to the chain:

```php
v::alnum()->noWhitespace->validate('foo 123'); //false
```

By default empty values are allowed, if you want
to invalidate them, add `->notEmpty()` to the chain:

```php
v::alnum()->notEmpty()->validate(''); //false
```

You can restrict case using the `->lowercase()` and
`->uppercase()` validators:

```php
v::alnum()->uppercase()->validate('aaa'); //false
```

Message template for this validator includes `{{additionalChars}}` as
the string of extra chars passed as the parameter.

See also:

  * [Alpha](Alpha.md)
  * [Digit](Digit.md)
  * [Consonant](Consonant.md)
  * [Vowel](Vowel.md)
