过滤，就是清除不需要的数据，留下想要的数据。
其调用方法如下，一：
$filter = new \Phalcon\Filter();
$filter->sanitize("some(one)@exa\mple.com", "email");
得到的结果是："someone@example.com"
另外一种方法是：
直接通过getPost/get获取
//gby(one)ftk\wf@qq.com
$email = $this->request->getPost("email", "email");
echo $email;
//gbyoneftkwf@qq.com
//$this->request->getPost("参数名", "email(需要验证的规则)");
自定义过滤器：
案一：
class IPv4Filter
{
public function filter($value)
{
return filter_var($value, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4);
}
}
$filter = new \Phalcon\Filter();
//Using an object
$filter->add(‘ipv4‘, new IPv4Filter());
//Sanitize with the "ipv4" filter
$filteredIp = $filter->sanitize("127.0.0.1", "ipv4");
案二：
$filter = new \Phalcon\Filter();
//Using an anonymous function
$filter->add(‘md5‘, function($value) {
return preg_replace(‘/[^0-9a-f]/‘, ‘‘, $value);
});
//Sanitize with the "md5" filter
$filtered = $filter->sanitize($possibleMd5, "md5");
The following are the built-in filters provided by this component:
| Name | Description |
|---|---|
| string | Strip tags |
| Remove all characters except letters, digits and !#$%&*+-/=?^_`{|}~@.[]. | |
| int | Remove all characters except digits, plus and minus sign. |
| float | Remove all characters except digits, dot, plus and minus sign. |
| alphanum | Remove all characters except [a-zA-Z0-9] |
| striptags | Applies the strip_tags function |
| trim | Applies the trim function |
| lower | Applies the strtolower function |
| upper | Applies the strtoupper function |
原文：http://www.cnblogs.com/achengmu/p/5914455.html