[php]php处理1970年前的日期方法源代码实例

我在处理一篇会员注册页面时，客户要求日期从1960年开始，这样就会产生以下问题：

Warning : date() [function.date ]: Windows does not support dates prior to midnight (00:00:00), January 1, 1970 in c:/program files/wamp/www/friends/admin/users_manager.php on line 320

Warning : date() [function.date ]: Windows does not support dates prior to midnight (00:00:00), January 1, 1970 in c:/program files/wamp/www/friends/admin/users_manager.php on line 321

Warning : date() [function.date ]: Windows does not support dates prior to midnight (00:00:00), January 1, 1970 in c:/program files/wamp/www/friends/admin/users_manager.php on line 322

在网上搜了半天，没找到合适的办法，于是千思万想，想到了以下的办法，解决了这个问题：

$sql_query="select * from members where mem_id='$mem_id'";   
            $mem=sql_execute($sql_query,'get');   
               
            //first check birthday if it is prior to 1970   
            if($mem->birthday<0)   
            {   
                //先加10年，有两个闰年，帮日加2.   
                $d=date("d",10*365*24*60*60+$mem->birthday)+2;   
                $m=date("m",10*365*24*60*60+$mem->birthday);   
                $y=date("y",10*365*24*60*60+$mem->birthday)-10;   
            }   
            else   
            {   
                $d=date("d",$mem->birthday);   
                $m=date("m",$mem->birthday);   
                $y=date("Y",$mem->birthday);   
            }