wp_nav_menu
函数
wp_nav_menu ( $args = array() )
- 参数
-
-
(array)
$args
{ Optional. Array of nav menu arguments. @type int|string|WP_Term $menu Desired menu. Accepts a menu ID, slug, name, or object. Default empty. @type string $menu_class CSS class to use for the ul element which forms the menu. Default 'menu'. @type string $menu_id The ID that is applied to the ul element which forms the menu. Default is the menu slug, incremented. @type string $container Whether to wrap the ul, and what to wrap it with. Default 'div'. @type string $container_class Class that is applied to the container. Default 'menu-{menu slug}-container'. @type string $container_id The ID that is applied to the container. Default empty. @type string $container_aria_label The aria-label attribute that is applied to the container when it's a nav element. Default empty. @type callable|false $fallback_cb If the menu doesn't exist, a callback function will fire. Default is 'wp_page_menu'. Set to false for no fallback. @type string $before Text before the link markup. Default empty. @type string $after Text after the link markup. Default empty. @type string $link_before Text before the link text. Default empty. @type string $link_after Text after the link text. Default empty. @type bool $echo Whether to echo the menu or return it. Default true. @type int $depth How many levels of the hierarchy are to be included. 0 means all. Default 0. Default 0. @type object $walker Instance of a custom walker class. Default empty. @type string $theme_location Theme location to be used. Must be registered with register_nav_menu() in order to be selectable by the user. @type string $items_wrap How the list items should be wrapped. Uses printf() format with numbered placeholders. Default is a ul with an id and class. @type string $item_spacing Whether to preserve whitespace within the menu's HTML. Accepts 'preserve' or 'discard'. Default 'preserve'. }
- Required: 否
- Default: array()
-
(array)
$args
{ Optional. Array of nav menu arguments. @type int|string|WP_Term $menu Desired menu. Accepts a menu ID, slug, name, or object. Default empty. @type string $menu_class CSS class to use for the ul element which forms the menu. Default 'menu'. @type string $menu_id The ID that is applied to the ul element which forms the menu. Default is the menu slug, incremented. @type string $container Whether to wrap the ul, and what to wrap it with. Default 'div'. @type string $container_class Class that is applied to the container. Default 'menu-{menu slug}-container'. @type string $container_id The ID that is applied to the container. Default empty. @type string $container_aria_label The aria-label attribute that is applied to the container when it's a nav element. Default empty. @type callable|false $fallback_cb If the menu doesn't exist, a callback function will fire. Default is 'wp_page_menu'. Set to false for no fallback. @type string $before Text before the link markup. Default empty. @type string $after Text after the link markup. Default empty. @type string $link_before Text before the link text. Default empty. @type string $link_after Text after the link text. Default empty. @type bool $echo Whether to echo the menu or return it. Default true. @type int $depth How many levels of the hierarchy are to be included. 0 means all. Default 0. Default 0. @type object $walker Instance of a custom walker class. Default empty. @type string $theme_location Theme location to be used. Must be registered with register_nav_menu() in order to be selectable by the user. @type string $items_wrap How the list items should be wrapped. Uses printf() format with numbered placeholders. Default is a ul with an id and class. @type string $item_spacing Whether to preserve whitespace within the menu's HTML. Accepts 'preserve' or 'discard'. Default 'preserve'. }
- 返回值
-
- (void|string|false) Void if 'echo' argument is true, menu output if 'echo' is false. False if there are no items or no menu was found.
- 定义位置
-
- wp-includes/nav-menu-template.php , line 57
- 引入
- 3.0.0
- 弃用
- -
wp_nav_menu: 这个函数用于在WordPress中显示一个导航菜单。它接受一些参数,包括菜单位置、菜单ID以及容器和菜单类名称。
显示分类法菜单项的元框。
function wp_nav_menu( $args = array() ) {
static $menu_id_slugs = array();
$defaults = array(
'menu' => '',
'container' => 'div',
'container_class' => '',
'container_id' => '',
'container_aria_label' => '',
'menu_class' => 'menu',
'menu_id' => '',
'echo' => true,
'fallback_cb' => 'wp_page_menu',
'before' => '',
'after' => '',
'link_before' => '',
'link_after' => '',
'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
'item_spacing' => 'preserve',
'depth' => 0,
'walker' => '',
'theme_location' => '',
);
$args = wp_parse_args( $args, $defaults );
if ( ! in_array( $args['item_spacing'], array( 'preserve', 'discard' ), true ) ) {
// Invalid value, fall back to default.
$args['item_spacing'] = $defaults['item_spacing'];
}
/**
* Filters the arguments used to display a navigation menu.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param array $args Array of wp_nav_menu() arguments.
*/
$args = apply_filters( 'wp_nav_menu_args', $args );
$args = (object) $args;
/**
* Filters whether to short-circuit the wp_nav_menu() output.
*
* Returning a non-null value from the filter will short-circuit wp_nav_menu(),
* echoing that value if $args->echo is true, returning that value otherwise.
*
* @since 3.9.0
*
* @see wp_nav_menu()
*
* @param string|null $output Nav menu output to short-circuit with. Default null.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
if ( null !== $nav_menu ) {
if ( $args->echo ) {
echo $nav_menu;
return;
}
return $nav_menu;
}
// Get the nav menu based on the requested menu.
$menu = wp_get_nav_menu_object( $args->menu );
// Get the nav menu based on the theme_location.
$locations = get_nav_menu_locations();
if ( ! $menu && $args->theme_location && $locations && isset( $locations[ $args->theme_location ] ) ) {
$menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
}
// Get the first menu that has items if we still can't find a menu.
if ( ! $menu && ! $args->theme_location ) {
$menus = wp_get_nav_menus();
foreach ( $menus as $menu_maybe ) {
$menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) );
if ( $menu_items ) {
$menu = $menu_maybe;
break;
}
}
}
if ( empty( $args->menu ) ) {
$args->menu = $menu;
}
// If the menu exists, get its items.
if ( $menu && ! is_wp_error( $menu ) && ! isset( $menu_items ) ) {
$menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
}
/*
* If no menu was found:
* - Fall back (if one was specified), or bail.
*
* If no menu items were found:
* - Fall back, but only if no theme location was specified.
* - Otherwise, bail.
*/
if ( ( ! $menu || is_wp_error( $menu ) || ( isset( $menu_items ) && empty( $menu_items ) && ! $args->theme_location ) )
&& isset( $args->fallback_cb ) && $args->fallback_cb && is_callable( $args->fallback_cb ) ) {
return call_user_func( $args->fallback_cb, (array) $args );
}
if ( ! $menu || is_wp_error( $menu ) ) {
return false;
}
$nav_menu = '';
$items = '';
$show_container = false;
if ( $args->container ) {
/**
* Filters the list of HTML tags that are valid for use as menu containers.
*
* @since 3.0.0
*
* @param string[] $tags The acceptable HTML tags for use as menu containers.
* Default is array containing 'div' and 'nav'.
*/
$allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
if ( is_string( $args->container ) && in_array( $args->container, $allowed_tags, true ) ) {
$show_container = true;
$class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-' . $menu->slug . '-container"';
$id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
$aria_label = ( 'nav' === $args->container && $args->container_aria_label ) ? ' aria-label="' . esc_attr( $args->container_aria_label ) . '"' : '';
$nav_menu .= '<' . $args->container . $id . $class . $aria_label . '>';
}
}
// Set up the $menu_item variables.
_wp_menu_item_classes_by_context( $menu_items );
$sorted_menu_items = array();
$menu_items_tree = array();
$menu_items_with_children = array();
foreach ( (array) $menu_items as $menu_item ) {
$sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
$menu_items_tree[ $menu_item->ID ] = $menu_item->menu_item_parent;
if ( $menu_item->menu_item_parent ) {
$menu_items_with_children[ $menu_item->menu_item_parent ] = 1;
}
// Calculate the depth of each menu item with children
foreach ( $menu_items_with_children as $menu_item_key => &$menu_item_depth ) {
$menu_item_parent = $menu_items_tree[ $menu_item_key ];
while ( $menu_item_parent ) {
$menu_item_depth = $menu_item_depth + 1;
$menu_item_parent = $menu_items_tree[ $menu_item_parent ];
}
}
}
// Add the menu-item-has-children class where applicable.
if ( $menu_items_with_children ) {
foreach ( $sorted_menu_items as &$menu_item ) {
if (
isset( $menu_items_with_children[ $menu_item->ID ] ) &&
( $args->depth <= 0 || $menu_items_with_children[ $menu_item->ID ] < $args->depth )
) {
$menu_item->classes[] = 'menu-item-has-children';
}
}
}
unset( $menu_items_tree, $menu_items_with_children, $menu_items, $menu_item );
/**
* Filters the sorted list of menu item objects before generating the menu's HTML.
*
* @since 3.1.0
*
* @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
$items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
unset( $sorted_menu_items );
// Attributes.
if ( ! empty( $args->menu_id ) ) {
$wrap_id = $args->menu_id;
} else {
$wrap_id = 'menu-' . $menu->slug;
while ( in_array( $wrap_id, $menu_id_slugs, true ) ) {
if ( preg_match( '#-(d+)$#', $wrap_id, $matches ) ) {
$wrap_id = preg_replace( '#-(d+)$#', '-' . ++$matches[1], $wrap_id );
} else {
$wrap_id = $wrap_id . '-1';
}
}
}
$menu_id_slugs[] = $wrap_id;
$wrap_class = $args->menu_class ? $args->menu_class : '';
/**
* Filters the HTML list content for navigation menus.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$items = apply_filters( 'wp_nav_menu_items', $items, $args );
/**
* Filters the HTML list content for a specific navigation menu.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
// Don't print any markup if there are no items at this point.
if ( empty( $items ) ) {
return false;
}
$nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
unset( $items );
if ( $show_container ) {
$nav_menu .= '</' . $args->container . '>';
}
/**
* Filters the HTML content for navigation menus.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $nav_menu The HTML content for the navigation menu.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
if ( $args->echo ) {
echo $nav_menu;
} else {
return $nav_menu;
}
}
常见问题
FAQs-
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要使用`
get_users`函数获取所有用户列表,可以按照以下步骤进行:1. 使用`
get_users`函数调用获取用户列表:$users = get_users();
2. 您可以按需使用参数来过滤结果。例如,您可以通过角色、用户ID、用户登录名等过滤用户列表。以下是一个根据用户角色为过滤条件的示例:
$users = get_users( array( 'role' => 'subscriber' // 将角色名称替换为您要过滤的角色 ) );在上述示例中,将`
role`参数设置为所需的角色名称来过滤用户列表。3. 您可以使用循环遍历获取的用户列表,并访问每个用户的属性。例如,以下示例将显示每个用户的用户名和电子邮件地址:
foreach( $users as $user ) { echo '用户名:' . $user->user_login . ', 电子邮件:' . $user->user_email . ; }在上述示例中,通过`
$user->user_login`和`$user->user_email`访问每个用户的用户名和电子邮件地址。请注意,`
get_users`函数默认返回所有用户,并可以根据需要使用更多参数进行过滤。您可以参阅WordPress官方文档中的`get_users`函数文档,了解更多可用参数和用法示例。总结起来,使用`
get_users`函数获取所有用户列表的步骤是:- 调用`
get_users`函数获取用户列表。 - 使用可选的过滤参数,根据需要过滤用户列表。
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- 调用`
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在WordPress中,可以使用WP_PLUGIN_DIR和WP_PLUGIN_URL常量来定义插件的目录路径和URL。
1. `WP_PLUGIN_DIR`:这是一个常量,用于定义插件的目录路径(文件系统路径)。您可以使用以下代码在插件文件中访问该常量:
$plugin_dir = WP_PLUGIN_DIR . '/your-plugin-folder/';
在上述代码中,将"your-plugin-folder"替换为您插件的实际文件夹名称。使用该常量,您可以获取插件文件的完整路径。
2. `WP_PLUGIN_URL`:这是一个常量,用于定义插件的URL(用于在网页上访问插件文件)。以下是一个使用该常量的示例:
$plugin_url = WP_PLUGIN_URL . '/your-plugin-folder/';
同样,请将"your-plugin-folder"替换为您插件的实际文件夹名称。使用该常量,您可以获取插件在网页上的完整URL。
请注意,`WP_PLUGIN_DIR`和`WP_PLUGIN_URL`常量在WordPress版本2.6之后引入。从WordPress 5.5版本开始,这两个常量被标记为过时(deprecated),因为WordPress更倾向于使用新的插件文件结构。如果您正在开发新插件,建议使用新的插件文件结构和相关函数。
在新的插件文件结构中,可以使用以下函数来获取插件的目录路径和URL:
- `plugin_dir_path()`:获取插件目录路径。
- `plugin_dir_url()`:获取插件URL。这些函数会自动将插件的版本、多站点和SSL等考虑因素纳入计算。
总结起来,使用`WP_PLUGIN_DIR`和`WP_PLUGIN_URL`常量定义插件的目录和URL的方法是:
$plugin_dir = WP_PLUGIN_DIR . '/your-plugin-folder/'; $plugin_url = WP_PLUGIN_URL . '/your-plugin-folder/';
但请注意,这两个常量已被标记为过时,建议使用新的插件文件结构和相关函数来获取插件的路径和URL。
-
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使用PHP在WordPress中添加自定义功能可以通过以下方式实现:
- 创建一个自定义插件,将功能代码添加到插件中。
- 使用WordPress的钩子系统,将自定义功能绑定到适当的钩子上。
- 在主题文件中添加自定义功能代码,例如functions.php文件。
- 使用WordPress的短代码功能,将自定义功能封装为短代码。
- 使用WordPress的插件或主题编辑器,将自定义功能代码添加到适当的位置。
下面是一个实操示例。
要在WordPress中添加自定义功能,可以按照以下步骤使用PHP编写并添加自定义功能:
- 打开WordPress安装目录中的主题文件夹,通常位于wp-content/themes/下,找到正在使用的主题文件夹。
- 在主题文件夹中,可以创建一个名为functions.php的文件。如果该文件已经存在,可以直接编辑它。
- 在functions.php文件中,可以使用PHP代码添加自定义功能。以下是一些常见的示例:
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请注意,修改主题文件可以在主题更新时丢失,因此建议在进行任何更改之前备份functions.php文件。此外,为避免不必要的错误和冲突,建议在添加自定义功能前先了解WordPress开发文档和最佳实践,以确保正确、安全地实现所需的自定义功能。
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如何使用do_action来触发一个钩子函数?
使用
do_action函数可以触发一个钩子函数。do_action函数的参数与要触发的钩子函数的参数相同。例如,触发save_post钩子函数的代码如下:
do_action( 'save_post', $post_ID, $post );
这里,
$post_ID和$post是传递给钩子函数的参数。 -
如何使用wp_get_current_user获取当前登录用户的信息?
使用
wp_get_current_user获取当前登录用户的信息:$current_user = wp_get_current_user(); // 获取当前用户的ID $user_id = $current_user->ID; // 获取当前用户的用户名 $user_login = $current_user->user_login; // 获取当前用户的邮箱 $user_email = $current_user->user_email; // 获取当前用户的显示名称 $display_name = $current_user->display_name;
