获取数组中特定键的数据，并进行默认值设置

filter_array.php

<?php
/**
 * @author 胡泽民 <huzemin8@126.com>
 */

// 获取数组中特定键的数据，并进行默认值设置
function filter_array($params, $keys) {
    if(!is_array($params)) {
        return null;
    }
    if(!is_array($keys)) {
        $keys = explode(',', $keys);
        $_keys = array();
        foreach($keys as $k => $v) {
            $v = explode('#', $v);
            if(count($v) == 2) {
                $_keys[trim($v[0])] = trim($v[1]);
            } else {
                $_keys[trim($v[0])] = null;
            }
        }
        $keys = $_keys;
        unset($_keys);
    }
    if(count($keys) > 0) {
        $_params = array();

        foreach($keys as $k => $v) {
            if(isset($params[$k])) {
                $_params[$k] = $params[$k];
            } else {
                $_params[$k] = $v;
            }
        }
        return $_params;
    }

    return $params;
}