function get_categories_tree($cat_id = 0)
{
    if ($cat_id > 0)
    {
        $sql = 'SELECT parent_id FROM ' . $GLOBALS['ecs']->table('category') . " WHERE cat_id = '$cat_id'";
        $parent_id = $GLOBALS['db']->getOne($sql);
    }
    else
    {
        $parent_id = 0;
    }

    /*
     判断当前分类中全是是否是底级分类，
     如果是取出底级分类上级分类，
     如果不是取当前分类及其下的子分类
    */
    $sql = 'SELECT count(*) FROM ' . $GLOBALS['ecs']->table('category') . " WHERE parent_id = '$cat_id' AND is_show = 1 ";
    if ($GLOBALS['db']->getOne($sql) || $parent_id == 0)
    {
        /* 获取当前分类及其子分类 */
        $sql = 'SELECT a.cat_id, a.cat_name, a.sort_order AS parent_order, a.cat_id, a.is_show,' .
                    'b.cat_id AS child_id, b.cat_name AS child_name, b.sort_order AS child_order ' .
                'FROM ' . $GLOBALS['ecs']->table('category') . ' AS a ' .
                'LEFT JOIN ' . $GLOBALS['ecs']->table('category') . ' AS b ON b.parent_id = a.cat_id AND b.is_show = 1 ' .
                "WHERE a.parent_id = '$parent_id' ORDER BY parent_order ASC, a.cat_id ASC, child_order ASC";
    }
    else
    {
        /* 获取当前分类及其父分类 */
        $sql = 'SELECT a.cat_id, a.cat_name, b.cat_id AS child_id, b.cat_name AS child_name, b.sort_order, b.is_show ' .
                'FROM ' . $GLOBALS['ecs']->table('category') . ' AS a ' .
                'LEFT JOIN ' . $GLOBALS['ecs']->table('category') . ' AS b ON b.parent_id = a.cat_id AND b.is_show = 1 ' .
                "WHERE b.parent_id = '$parent_id' ORDER BY sort_order ASC";
    }
    $res = $GLOBALS['db']->getAll($sql);

    $cat_arr = array();
    foreach ($res AS $row)
    {
        if ($row['is_show'])
        {
            $cat_arr[$row['cat_id']]['id']   = $row['cat_id'];
            $cat_arr[$row['cat_id']]['name'] = $row['cat_name'];
            $cat_arr[$row['cat_id']]['url']  = build_uri('category', array('cid' => $row['cat_id']), $row['cat_name']);

            if ($row['child_id'] !NULLbr />             {
                                $cat_id = $row['child_id'];
                $sql = "select count(*) as num from ".$GLOBALS['ecs']->table('goods')." where cat_id='$cat_id' and is_on_sale = 1 AND is_alone_sale = 1 AND is_delete = 0 ";
                                $num = $GLOBALS['db']->getOne($sql);
                                $cat_arr[$row['cat_id']]['children'][$row['child_id']]['num']   = $num;
                $cat_arr[$row['cat_id']]['children'][$row['child_id']]['id']   = $row['child_id'];
                $cat_arr[$row['cat_id']]['children'][$row['child_id']]['name'] = $row['child_name'];
                $cat_arr[$row['cat_id']]['children'][$row['child_id']]['url']  = build_uri('category', array('cid' => $row['child_id']), $row['child_name']);
            }
        }
    }

    return $cat_arr;
}

/*------------------------------------增加以下SQL语句--------------------------------------------*/

$sql = "select count(*) as num from ".$GLOBALS['ecs']->table('goods')." where cat_id='$cat_id' and is_on_sale = 1 AND is_alone_sale = 1 AND is_delete = 0 ";
                                $num = $GLOBALS['db']->getOne($sql);
                                $cat_arr[$row['cat_id']]['children'][$row['child_id']]['num']   = $num;