# Alnum - `v::alnum()` - `v::alnum(string $additionalChars)` Validates alphanumeric characters from a-Z and 0-9. ```php v::alnum()->validate('foo 123'); // true v::alnum()->validate('number 100%'); // false v::alnum('%')->validate('number 100%'); // true ``` Because this rule allows whitespaces by default, you can separate additional characters with a whitespace: ```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 ``` 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) * [Charset](Charset.md) * [Cntrl](Cntrl.md) * [Consonant](Consonant.md) * [Digit](Digit.md) * [NoWhitespace](NoWhitespace.md) * [Regex](Regex.md) * [StringType](StringType.md) * [Vowel](Vowel.md) * [Xdigit](Xdigit.md)