二维数组按照某个键值排序

//二维数组，按其中某个键值排序
/*
* @param array $array the array to sort.
* @param string $key_name the first item to sort by.
* @param string $sort_order the order to sort by("SORT_ASC"|"SORT_DESC")
* @param string $sort_type the sort type("SORT_REGULAR"|"SORT_NUMERIC"|"SORT_STRING")
*/
function multisort(&$array, $key_name, $sort_order = 'SORT_ASC', $sort_type = 'SORT_REGULAR') {
    if (!is_array($array)) {
        return $array;
    }
    
    // Get args number.
    $arg_count = func_num_args();
    
    // Get keys to sort by and put them to SortRule array.
    for ($i = 1; $i < $arg_count; $i++) {
        $arg = func_get_arg($i);
        if (!eregi('SORT', $arg)) {
            $key_name_list[] = $arg;
            $sort_rule[] = '$'.$arg;
        } else {
            $sort_rule[] = $arg;
        }
    }
    
    // Get the values according to the keys and put them to array.
    foreach ($array as $key => $info) {
        foreach ($key_name_list as $key_name) {
            ${$key_name}[$key] = $info[$key_name];
        }
    }
    
    // Create the eval string and eval it.
    $eval_str = 'array_multisort('.implode(',', $sort_rule).', $array);';
    eval($eval_str);
    return $array;

}

　　例子

$data =  Array
        (
        0 => Array
            (
            'title' => '<font color="red">U8</font>-HR宁夏',
            'linkline' => 'space.php?uid=4018&do=album&id=498',
            'time' => 1275012236,
            'content' => '<font color="red">U8</font>-HR宁夏',
            'from' => 'album'
            ),
        1 => Array
            (
            'title' => '<font color="red">u8</font> AII-in-One全国巡展-济宁站',
            'linkline' => 'space.php?uid=2770&do=album&id=339',
            'time' => 1268628887,
            'content' => '<font color="red">u8</font> AII-in-One全国巡展-济宁站',
            'from' => 'album'
            ),
        2 => Array
            (
            'title' => '<font color="red">U8</font> ALL-IN-ONE巡展-河南站',
            'linkline' => 'space.php?uid=1282&do=album&id=359',
            'time' => 1269333609,
            'content' => '<font color="red">U8</font> ALL-IN-ONE巡展-河南站',
            'from' => 'album'
            ),
        3 => Array
            (
            'title' => '先睹为快 <font color="red">U8</font> All-in-One体验光盘',
            'linkline' => 'space.php?uid=3857&do=album&id=665',
            'time' => 1285049939,
            'content' => '先睹为快 <font color="red">U8</font> All-in-One体验光盘',
            'from' => 'album'
            )
        )
multisort($data, 'time', 'SORT_DESC');