如何在SQLite中重命名索引？(How to rename an index in SQLite?)

 菜单不完整，你只是没有正确检查代码。 
 
 以下代码将加载菜单的数组。 该数组包含构建菜单所需的全部信息。 然后，您可以递归地循环访问数组，以使用您需要的HTML结构来构建菜单。 如果您将此菜单添加到现有菜单中，这很有用，因为它允许您匹配现有菜单使用的HTML结构。 
 
// This uses the object manager
// A better way would be to inject the MenuFactory in your constructor
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$menu = $objectManager->create('FishPig\WordPress\Model\MenuFactory')->create();

$menuId = 3;

if ($menu->load($menuId)->getId()) {
    echo sprintf('<pre>%s</pre>', print_r($menu->getMenuTreeArray(), true));
}
else {
    echo 'No menu exists in WordPress with an ID of ' . (int)$menuId;
}
 
 如果您不关心使用哪种HTML结构，则可以使用以下块： 
 
\FishPig\WordPress\Block\Sidebar\Widget\NavMenu
 
 如果您查看该块的代码，您会看到它检查数据项“nav_menu”以获取菜单ID。 你可以通过XML来设置它（如果你通过XML创建块）或者使用PHP创建整个事物： 
 
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$menuBlock = $objectManager->create('FishPig\WordPress\Block\Sidebar\Widget\NavMenuFactory')->create();

$menuId = 3;

echo $menuBlock->setNavMenu($menuId)->toHtml();
 
 这个解决方案不如原来的解决方案好，因为它迫使你使用特定的HTML结构。 使用第一种解决方案会更好，因为这可以让您使用任何您需要的HTML结构。 你的主题可能已经有一个CSS规则和JS的菜单，所以你可以使用这个方法在正确的HTML结构中建立菜单。 

Menu's are not incomplete, you just haven't checked the code properly.
 
The following code will load an array of the menu. This array contains all of the information you need to build the menu. You can then recursively loop through the array to build the menu using the HTML structure that you require. This is useful if you are adding this menu to an existing menu as it allows you to match the HTML structure used by your existing menu.
 
// This uses the object manager
// A better way would be to inject the MenuFactory in your constructor
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$menu = $objectManager->create('FishPig\WordPress\Model\MenuFactory')->create();

$menuId = 3;

if ($menu->load($menuId)->getId()) {
    echo sprintf('<pre>%s</pre>', print_r($menu->getMenuTreeArray(), true));
}
else {
    echo 'No menu exists in WordPress with an ID of ' . (int)$menuId;
}
 
If you don't care what HTML structure is used, you can use the following block:
 
\FishPig\WordPress\Block\Sidebar\Widget\NavMenu
 
If you look through the code of this block, you will see it checks the data item 'nav_menu' for the menu ID. You can set this via XML (if you created the block via XML) or create the whole thing using PHP:
 
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$menuBlock = $objectManager->create('FishPig\WordPress\Block\Sidebar\Widget\NavMenuFactory')->create();

$menuId = 3;

echo $menuBlock->setNavMenu($menuId)->toHtml();
 
This solution isn't as good as the original solution though as it forces you to use a specific HTML structure. You would be much better using the first solution, as this will allow you to use any HTML structure that you require. Your theme probably already has a menu with CSS rules and JS in place so you could use this method to build the menu in the correct HTML structure.