PHP格式检查类

<?php
/**
 * input:php格式检查类
 * 用法:
 * require_once('../src/input.class.php');
   $arr=array(
        array('name','username'),
        array('email','email'),
        array('tel','notempty')
    );
    $i=new input;
    $data=$i->create($arr);
    if(!$data){
        echo $i->error_field;
    }else{
        print_r($data);
    }
 **/
class input
{
    public $error_field='';
    public function create($arr,$m='post')
    {
        $M=($m==='post')?$_POST:$_GET;
        foreach($arr as $var){
            if(method_exists($this,$var[1])){
                if(isset($M[$var[0]]) and $this->$var[1]($M[$var[0]])){}
                else{
                    $this->error_field=$var[0];
                    return false;
                }
            }
        }
        return $M;
    }

    public function notempty($str){
        return !empty($str);
    }
    public function email($str){
        return is_string($str)&&preg_match('/^[_\.0-9a-z-]+@([0-9a-z][0-9a-z-]+\.)+[a-z]{2,4}$/',$str);
    }
    public function url($str){
        return is_string($str)&&preg_match("/^http:\/\/[A-Za-z0-9]+\.[A-Za-z0-9]+[\/=\?%\-&_~`@[\]\':+!]*([^<>\"\"])*$/",$str);
    }
    public function phone($str){
        return preg_match('/^((\(\d{3}\))|(\d{3}\-))?(\(0\d{2,3}\)|0\d{2,3}-)?[1-9]\d{6,7}$/',$str);
    }
    public function ip($ip){
        return preg_match("/^([1-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])" . "(\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}$/", $ip);
    }
    public function date($var){
        return preg_match("/([0-9]{4})-([0-9]{1,2})-([0-9]{1,2})/",$var);
    }
    public function color($var){
        return preg_match("/^#?([a-f]|[A-F]|[0-9]){3}(([a-f]|[A-F]|[0-9]){3})?$/",$var);
    }
    public function username($var){
        return preg_match("/^[a-zA-Z0-9_\.\-]{3,16}$/",$var);
    }
    public function pic($var){
        return preg_match("/^[a-zA-Z0-9\-\.]+\.(jpg|jpeg|gif|png)$/",$var);
    }
    public function tel($str)
    {
        return preg_match("/^((13[0-9])|(15[^4,\\D])|(18[0,5-9]))\\d{8}$/",$str);
    }
}