php 获取当天或某个日期是星期几

效果：

今天是：星期五

今天是：礼拜五

2012-12-12是：礼拜日

<?php
function getWeekName($data,$format = '星期')
{
    $week   =  date( "D ",$data); 
    switch($week) 
    { 
        case "Mon ": 
            $current   =   $format."一"; 
            break; 
        case "Tue ": 
            $current   =   $format."二"; 
            break; 
        case "Wed ": 
            $current   =   $format."三"; 
            break; 
        case "Thu ": 
            $current   =   $format."四"; 
            break; 
        case "Fri ": 
            $current   =   $format."五"; 
            break; 
        case "Sat ": 
            $current   =   $format."六"; 
            break; 
        case "Sun ": 
            $current   =   $format."日"; 
            break; 
    } 
    return $current;
}

echo '今天是：'.getWeekName(time(),'星期');
echo '<br>';
echo '今天是：'.getWeekName(time(),'礼拜');
echo '<br>';
echo '2010-12-12是：'.getWeekName(strtotime('2010-12-12'),'礼拜');
?>
//该片段来自于http://outofmemory.cn