php相对目录比较

$a = '/e/a/b/d.php';$b = '/a/b/12/34/b/d/c.php';function get_ret_path($a,$b){$a = trim($a,'/');$b = trim($b,'/');$ad = dirname($a);$bd = dirname($b);$arr_a = explode('/',$ad);$arr_b = explode('/',$bd);//从前面开始比起，找到不同位置$position = 0;foreach($arr_a as $key => $dir){if($arr_a[$key] == $dir){$position = $key;}else{break;}}//echo $position;//$a相对于$b//取b的该位置的相对目录//+1是文件自身目录$prefix = str_repeat("../",count($arr_b)-$position+1);$ext = implode('/',array_slice($arr_a,$position));return $prefix.$ext.'/'.basename($a);}echo get_ret_path($a,$b);

N年前看到过这个题目，今天再写一次