從 php 5.2 版起新增的功能, filter_var: http://php.net/manual/en/function.filter-var.php
使用方式如:
filter_var('[email protected]', FILTER_VALIDATE_EMAIL)
用來檢查是否為 email 字串, 若是則會回傳該 string [true], 若否則會回傳 false.
其中的 filter type 有 http://www.php.net/manual/en/filter.filters.php
例如:
只用來檢查:
FILTER_VALIDATE_BOOLEAN
FILTER_VALIDATE_EMAIL
FILTER_VALIDATE_FLOAT
FILTER_VALIDATE_INT
FILTER_VALIDATE_IP
FILTER_VALIDATE_REGEXP
FILTER_VALIDATE_URL
用來整理(也就是把不合法字元去除, 對於一些過濾應用很方便):
FILTER_SANITIZE_EMAIL
FILTER_SANITIZE_ENCODED
FILTER_SANITIZE_MAGIC_QUOTES
FILTER_SANITIZE_NUMBER_FLOAT
FILTER_SANITIZE_NUMBER_INT
FILTER_SANITIZE_SPECIAL_CHARS
FILTER_SANITIZE_FULL_SPECIAL_CHARS
FILTER_SANITIZE_STRING
FILTER_SANITIZE_STRIPPED
FILTER_SANITIZE_URL
FILTER_UNSAFE_RAW
還有 call_back 應用及 flag 可以組合出更好的應用. 十分方便.