数组树函数

function getTree($data, $pid = 0, $key = ‘id‘, $pKey = ‘pid‘, $childKey = ‘child‘, $maxDepth = 0){
	static $depth = 0;
	$depth++;
	if (intval($maxDepth) <= 0)
	{
		$maxDepth = count($data) * count($data);
	}
	if ($depth > $maxDepth)
	{
		exit("error recursion:max recursion depth {$maxDepth}");
	}
	$tree = array();
	foreach ($data as $rk => $rv)
	{
		if ($rv[$pKey] == $pid)
		{
			$rv[$childKey] = getTree($data, $rv[$key], $key, $pKey, $childKey, $maxDepth);
			$tree[] = $rv;
		}
	}
	return $tree;
}