Zencart的模板初始导航是没有下拉功能的，今天我们就看看二级目录导航如何下拉。

Zencart的模板初始导航一般都是在tpl_header.php中调用tpl_top_nav.php这个文件，今天我们所写的代码是在tpl_header.php中直接写的，tpl_header.php的路劲是/includes/templates/你的模板/common/里面的。

下面我们看看代码如何编写：

<?php

$order_by = " order by a.sort_order, b.categories_name ";

$categories_tab_query = "select a.categories_id,b.categories_name from " .

TABLE_CATEGORIES . " a, " . TABLE_CATEGORIES_DESCRIPTION . " b where a.categories_id=b.categories_id and a.parent_id= '0' and a.cat_rec_new= '1' and b.language_id='" . (int)$_SESSION['languages_id'] . "' and a.categories_status='1'" .

$order_by;

$categories_tab = $db->Execute($categories_tab_query);

//echo count($categories_tab->fields['categories_name']);

while(!$categories_tab->EOF) {

$catecontent .= '<li class="mu_nav_ico"><a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . (int)$categories_tab->fields['categories_id']) . '"><span>'.$categories_tab->fields['categories_name'].'</span></a>' . "\n";

//====================2

$pid = $categories_tab->fields['categories_id'];

$sql = "select a.categories_id,b.categories_name from " .

TABLE_CATEGORIES . " a, " . TABLE_CATEGORIES_DESCRIPTION . " b where a.categories_id=b.categories_id and a.parent_id= '".(int)$categories_tab->fields['categories_id']."' and b.language_id='" . (int)$_SESSION['languages_id'] . "' and a.categories_status='1'" .$order_by."";

$categories_main = $db->Execute($sql);

if(!$categories_main->EOF){

$catecontent .= '<ul>' . "\n";

while(!$categories_main->EOF) {

$catecontent .= '<li><a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . (int)$categories_tab->fields['categories_id'].'_'.$categories_main->fields['categories_id']) . '">'.$categories_main->fields['categories_name'].'</a></li>' . "\n";

$categories_main->MoveNext();

}

$catecontent .= '</ul>' . "\n";

}

$catecontent .= '</li>' . "\n";

$categories_tab->MoveNext();

}

echo $catecontent;

?>

我们只需要把这串代码放入导航对应的代码即可。

这里需要注意的是样式以及js需要自己去编写的。具体的js和样式我们下篇文章再来告诉大家