Question

这是我将导航栏存储到会话

的功能

function menu($sp_id,$offset = 0, $ulclass, $liclass) {
        $menudb =new db;

        if($offset == 0)
            $_SESSION['nav_menu'].= "<ul class=\"sf-menu\">";

        if($sp_id == 0)
        {
            $sql = "SELECT `label`, `link` , `sp_id` FROM `nav_menu` ORDER BY `sort` ASC LIMIT $offset,100000000000000";
            $menudb->query($sql);

            while ($row = $menudb->result()->fetch_assoc()) {
                $offset++;
                $_SESSION['nav_menu'].= "<li class=\"$liclass\"><a href='" . $row['link'] . "'>" . $row['label'] . "</a>";

                if($row['sp_id'] != 0){
                    $_SESSION['nav_menu'].= "<div class=\"mobnav-subarrow\"></div>";
                     menu($row['sp_id'],$offset, $ulclass, $liclass);
                }
                else
                    $_SESSION['nav_menu'].="</li>";
            }
        }
        else
        {
            $sql = "SELECT `bt_name` AS label FROM `business_sub_type` WHERE `sp_id` = $sp_id OR `sp_id` = 0";
            $menudb->query($sql);

            $_SESSION['nav_menu'].= "<ul class=\"sf-menu\">";

            while ($row = $menudb->result()->fetch_assoc()) {
                $_SESSION['nav_menu'].= "<li class=\"$liclass\"><a href='#'>" . $row['label'] . "</a></li>";
            }
            $_SESSION['nav_menu'].= "</ul></li>";
            menu(0,$offset, $ulclass, $liclass);
        }
        $_SESSION['nav_menu'].= "</ul>";
//here
}

现在我希望我的函数应该在//这里无论何时来/这里都会以任何代价死去。但它会一次又一次地重复自身和会话存储菜单，

如果这是通过将菜单保存到会话来减少加载时间的正确方法，还请指导我吗？感谢

Answer 1

你甚至不需要递归来做你正在做的事情。如果你有一个多层数据库结构，最初没有设置深度，你应该使用递归。在您的情况下，您似乎只有两个级别：'nav_menu'数据库表和'business_sub_type'数据库表，与第一个相关。您所要做的就是循环浏览'nav_menu'，并且每个人都循环访问与之相关的'business_sub_type。

只需将您的功能更改为

function menu() {
    $menudb =new db;
    $submenu = new db;
    $_SESSION['nav_menu'] = "<ul class=\"sf-menu\">";
    // get all nav_menu items ordered by 'sort' column
    $sql = "SELECT `label`, `link` , `sp_id` FROM `nav_menu` ORDER BY `sort` ASC";
    $menudb->query($sql);
    while ($row = $menudb->result()->fetch_assoc()) {
        $_SESSION['nav_menu'].= "<li class=\"li-menu\"><a href='" . $row['link'] . "'>" . $row['label'] . "</a>";

        if($row['sp_id'] != 0){
            $_SESSION['nav_menu'].= "<div class=\"mobnav-subarrow\"></div>";
            // get all 'business_sub_type' for this nam_menu
            $sql = "SELECT `bt_name` AS label FROM `business_sub_type` WHERE `sp_id` = ".$row['sp_id']." OR `sp_id` = 0";
            // I am not sure the ' OR `sp_id` = 0' part is correct at all 
            $submenu->query($sql);
            $_SESSION['nav_menu'].= "<ul class=\"sf-menu\">";
            while ($row1 = $submenu->result()->fetch_assoc()) {
                $_SESSION['nav_menu'].= "<li class=\"li-menu\"><a href='#'>" . $row1['label'] . "</a></li>";
            }
            $_SESSION['nav_menu'].="</ul></li>";
        }
        else
        {
            $_SESSION['nav_menu'].="</li>";
        }
    }

    $_SESSION['nav_menu'].= "</ul>";
}

并回答关于递归的问题。你通过不在内部调用它来停止递归。或者换句话说，定义一个逻辑分支，如果不满足或满足某些条件，则不会自动调用递归函数。

在PHP中强制停止递归

1 个答案: