この質問の本来の意図は、単一の投稿がどこから参照されたかを知り、それに従って、投稿リファラーに従って次の投稿と前の投稿を提供することでした。
私が達成したかったのは、たとえば次のとおりでした。
カテゴリ、分類、タグ、検索、または作成者のアーカイブページから投稿をクリックします。これらのアーカイブはリファラーとして機能します。さて、通常は、私の質問のように、wp_get_referer()
そのリファラーを取得し、それをさらにクエリで使用するために使用します。上記の受け入れられた回答で@GMによって説明されているように、この方法は信頼できないため、私は彼の代替ソリューションを使用しました。
もう1つの問題は、特定のアーカイブからクリックされた元の単一の投稿から移動するときに元のリファラーからの投稿を処理するために、このリファラーを保存するために何らかのCookieまたはセッションを使用する必要があったことです。Cookieもエンドユーザーによって制御されるため、信頼できないため、WordPressはデフォルトでセッションを使用しないため、@ GM Alternative Solutionを使用して次の投稿リンクと前の投稿リンクをリファクタリングし、オリジナルをチェックして保存する信頼できる方法を用意しましたリファラー。
これが私が思いついたものであり、近い将来誰かがそれを役に立つと思うことを願っています。ニーズに合わせてコードを使用および悪用してください。リクエストは1つだけです。この質問へのリンクを残してください。:-)
フォローするコードに関する注意事項
このコードは非常に長くて集中的であるため、詳細には触れません。コードはよくコメントされています
このコードには、WordPressのデフォルトnext_post_link()
およびprevious_post_link()
機能と同じように、同じ用語内の投稿間をページ移動するオプションがあります。ネイティブ関数と同様に、分類法を設定する必要があります。のデフォルト値in_same_term
はでtrue
あり、分類法はcategory
最も重要なことには、このコードにはPHP 5.4+が必要です。
コード
<?php
/**
* @author Pieter Goosen
* @license GPLv2
* @link http://www.gnu.org/licenses/gpl-2.0.html
*
* The functions on this page returns the next and previous post links
* depending on what has been set
*
* @return function single_post_navigation()
*/
/**
* Register six new query variables aq, ,cq, tq, ttq, taq, and sq set by
* the term_referer_link function
*
* @see http://codex.wordpress.org/WordPress_Query_Vars
*
*/
add_filter( 'query_vars', function ( $vars ) {
$vars[] = 'cq'; // Will hold category ID
$vars[] = 'tq'; // Will hold taxonomy name
$vars[] = 'ttq'; // Will hold term slug
$vars[] = 'sq'; // Will hold search query
$vars[] = 'aq'; // Will hold author name
$vars[] = 'taq'; // Will hold tag id
return $vars;
}, 10, 3 );
/**
* Conditional tag to check whether or not a query_var has been set
*
* @param string $query_var query_var to check
* @return (bool) true if query_var exists, false on failure
*
*/
function has_query_var( $query_var ) {
$array = $GLOBALS['wp_query']->query_vars;
return array_key_exists( $query_var, $array );
}
/**
* For posts being clicked from a category page, the query_var, 'cq' is set.
* 'cq' holds the category ID
*
* Set two query_var, 'tq' and 'ttq' to single posts that was clicked on from
* taxonomy pages. 'tq' holds the taxonomy name while 'ttq' holds the term name
*
* For search queries, the query_var, 'sq' is set to single posts that was clicked on from
* the search page. 'sq' holds the search query value
*
* For posts being clicked from an author page, the query_var, 'aq' is set.
* 'aq' holds the author ID
*
* For posts being clicked from a tag page, the query_var, 'taq' is set.
* 'taq' holds the tag ID
*
* This function replaces the wp_get_referer() and $_SERVER['HTTP_REFERER']
* functions that are not very reliable
* @see php.net manual $_SERVER['HTTP_REFERER']
* @link http://php.net/manual/en/reserved.variables.server.php
*
* @uses add_query_arg()
* @uses post_link
* @uses post_type_link
*
*/
add_filter( 'post_type_link', 'term_referer_link', 10, 3 );
add_filter( 'post_link', 'term_referer_link', 10, 3 );
function term_referer_link( $permalink, $post ) {
switch ( true ) {
case ( is_category() ):
$category = get_queried_object_id();
$args = [
'cq' => $category,
];
break;
case ( is_tax() ):
$term = get_queried_object();
$args = [
'tq' => $term->taxonomy,
'ttq' => $term->slug
];
break;
case ( is_search() ):
$search = get_search_query();
$args = [
'sq' => $search,
];
break;
case ( is_author() ):
$author = get_queried_object_id();
$args = [
'aq' => $author,
];
break;
case ( is_tag() ):
$tag = get_queried_object_id();
$args = [
'taq' => $tag,
];
break;
}
if( isset( $args ) ) {
$permalink = add_query_arg( $args, $permalink );
}
return $permalink;
}
/**
* @access private
* This function is marked private and should not be used in any other functions
*
* This is a helper function for the main navigation function
*
* This function checks if any of the query variables is set in the single
* post page URL. If they exist, the values are retrieved that were set
* by the query variables
*
* These query variables are converted into query arguments for the query that will
* be used to determine the current post position and the posts adjacent to the
* current post which will translate in the next and previous post.
*
* When no query variables are present, an empty array of arguments is returned
*
* @uses has_query_var()
* @return (array) $add_query_args_to_args Query variable to determine the next/previous post links
* @see http://codex.wordpress.org/Function_Reference/add_query_arg
*
*/
function _query_vars_to_query_args() {
switch ( true ) {
case ( has_query_var( 'cq' ) ): // For category referrer
$category = get_query_var( 'cq' );
$add_query_args_to_args = [
'cat' => $category,
];
break;
case ( has_query_var( 'tq' ) && has_query_var( 'ttq' ) ): // For taxonomy term referrer
$taxonomy = get_query_var( 'tq' );
$term = get_query_var( 'ttq' );
$add_query_args_to_args = [
'tax_query' => [
[
'taxonomy' => $taxonomy,
'field' => 'slug',
'terms' => $term,
'include_children' => false,
],
],
];
break;
case ( has_query_var( 'sq' ) ): // For search referrer
$search = get_query_var( 'sq' );
$add_query_args_to_args = [
's' => $search,
];
break;
case ( has_query_var( 'aq' ) ): // For author referrer
$author = get_query_var( 'aq' );
$add_query_args_to_args = [
'author' => $author,
];
break;
case ( has_query_var( 'taq' ) ): // For tag referrer
$tag = get_query_var( 'taq' );
$add_query_args_to_args = [
'tag_id' => $tag,
];
break;
default: // Default: returns empty array on any other archive or homepage
$add_query_args_to_args = [];
break;
}
return $add_query_args_to_args;
}
/**
* @access private
* This function is marked private and should not be used in any other functions
*
* This is a helper function for the main pagination function. This function
* checks if the defined query variables has been set in the URL of a single
* post
*
* If any of the query variables are found on any given single post page, then
* these query variables will be set to the next and previous post links according
* to the single post's query variables
*
* This way, next and previous posts will be shown from the same category, term,
* search query or author archive from which the original single post was referred
* from.
*
* If a single post was referred from any other archive or main page, these query
* variables will not be set, and function will default to an empty array and no
* query variables will be set to the next and previous post links
*
* @uses has_query_var()
* @return (array) $qv Query variable to add to next/previous post links
* @see http://codex.wordpress.org/Function_Reference/add_query_arg
*
* @todo Other archives can be added later
*/
function _add_query_vars_to_nav_links() {
switch ( true ) {
case ( has_query_var( 'cq' ) ): // For category referrer
$category = get_query_var( 'cq' );
$qv = [
'cq' => $category,
];
break;
case ( has_query_var( 'tq' ) && has_query_var( 'ttq' ) ): // For taxonomy term referrer
$taxonomy = get_query_var( 'tq' );
$term = get_query_var( 'ttq' );
$qv = [
'tq' => $term->taxonomy,
'ttq' => $term->slug
];
break;
case ( has_query_var( 'sq' ) ): // For search referrer
$search = get_query_var( 'sq' );
$qv = [
'sq' => $search,
];
break;
case ( has_query_var( 'aq' ) ): // For author referrer
$author = get_query_var( 'aq' );
$qv = [
'aq' => $author,
];
break;
case ( has_query_var( 'taq' ) ): // For tag referrer
$tag = get_query_var( 'taq' );
$qv = [
'taq' => $tag,
];
break;
default: // Default: returns empty array on any other archive or homepage
$qv = [];
break;
}
return $qv;
}
/**
* This function returns navigation links to the next/previous single post
* There are choices to which taxonomy to use, and whether adjacent posts should
* be of the same term or not
*
* When in_same_term is set to true, you have a choice to use the parent term or
* child term if a post belongs to both. If the parent term is not available, the child term
* is automatically used
*
* @param array $defaults An array of key => value arguments. Defaults below
* - bool in_same_term Whether or not next/previous post should be in the same term Default true
* - bool parent_term If in_same_term is true, should the parent or child terms be used Default true
* - string/array taxonomy The taxonomy from which terms to use Default category
* - string/array post_types Post types to get posts from. Uses current post's post type on empty string. Default empty string
* - string previous_text Text to display with previous post Default 'Previous post'
* - string next_text Text to display with next post Default 'Next post'
*
* @return string $links
*/
function get_single_post_navigation( $args = [] ) {
// Sets the default arguments for default usage
$defaults = [
'in_same_term' => true,
'parent_term' => true,
'post_types' => '',
'taxonomy' => 'category',
'previous_text' => __( 'Previous post' ),
'next_text' => __( 'Next post' ),
];
// Merges the default arguments with user defined variables
$args = wp_parse_args( $args, $defaults );
/**
* Get the currently displayed single post. For this use
* get_queried_object() as this is more safe than the global $post
*
* The $post global is very easily changed by any poorly written custom query
* or function, and is there for not reliable
*
* @see Post below on WPSE for explanation
* @link /wordpress//q/167706/31545
*/
$single_post = get_queried_object();
/**
* Use the post type of the current post or post types entered in args
*
*/
$post_type = ( empty( $args['post_types'] ) ) ? $single_post->post_type : $args['post_types'];
// Set the variable query variables according to condition
if( !empty( _query_vars_to_query_args() ) ) {
$query_args = _query_vars_to_query_args();
}elseif( true === $args['in_same_term'] ) {
$terms = wp_get_post_terms( $single_post->ID, $args['taxonomy'] );
if ( ! empty( $terms ) && ! is_wp_error( $terms ) ){
foreach ( $terms as $term ) {
if( $term->parent === 0 ) {
$parent[] = $term;
}else{
$child[] = $term;
}
}
$term_id = ( $args['parent_term'] === true && isset( $parent ) ) ? $parent[0]->term_id : $child[0]->term_id;
$query_args = [
'tax_query' => [
[
'taxonomy' => $args['taxonomy'],
'field' => 'term_id',
'terms' => $term_id,
'include_children' => false,
],
],
];
}
}else{
$query_args = [];
}
// Default arguments to use with all the conditional statements above
$default_query_args = [
'post_type' => $post_type,
'fields' => 'ids',
'posts_per_page' => -1,
'suppress_filters' => true,
];
// Merges the default arguments with the arguments from the conditional statement
$combined_args = wp_parse_args( $query_args, $default_query_args );
$q = new WP_Query( $combined_args );
// Get the current post position. Will be used to determine adjacent posts
$current_post_position = array_search( $single_post->ID, $q->posts );
// Get the returned values from '_add_query_vars_to_nav_links()' to build links
$get_qv = _add_query_vars_to_nav_links();
// Get the next/older post ID
if ( array_key_exists( $current_post_position + 1 , $q->posts ) ) {
$next = $q->posts[$current_post_position + 1];
}
// Get post title link to the next post
if( isset( $next ) ) {
$next_post = get_post( $next );
$next_post_link = ( !empty( $get_qv ) ) ? add_query_arg( $get_qv, get_permalink( $next ) ) : get_permalink( $next );
$next_title = '<span class="meta-nav">' . $args['next_text'] . ': </span><a href="' . $next_post_link . '">' . $next_post->post_title . '</a></br>';
}else{
$next_title = '';
}
// Get the previous/newer post ID
if ( array_key_exists( $current_post_position - 1 , $q->posts ) ) {
$previous = $q->posts[$current_post_position - 1];
}
// Get post title link to the previous post
if( isset( $previous ) ) {
$previous_post = get_post( $previous );
$previous_post_link = ( !empty( $get_qv ) ) ? add_query_arg( $get_qv, get_permalink( $previous ) ) : get_permalink( $previous );
$previous_title = '<span class="meta-nav">' . $args['previous_text'] . ': </span><a href="' . $previous_post_link . '">' . $previous_post->post_title . '</a></br>';
}else{
$previous_title = '';
}
// Create the next/previous post links
$links = '<nav class="navigation post-navigation" role="navigation">';
$links .= '<div class="nav-links">';
$links .= $previous_title;
$links .= $next_title;
$links .= '</div><!-- .nav-links -->';
$links .= '</nav><!-- .navigation -->';
// Returns the post links with HTML mark-up
return $links;
}
/**
* This function is simply just a wrapper for the main navigation
* function and echo's the returned values from the main navigation
* function
*/
function single_post_navigation( $args = [] ) {
echo get_single_post_navigation( $args );
}
単一テンプレートでの使用
同じ用語内で投稿を移動する必要がなく、すべての投稿タイプから投稿を取得し、リンクを使用して次のテキストと前のテキストをカスタマイズする必要がある場合は、次の操作を実行できます。
$args = [
'in_same_term' => false,
'post_types' => ['post', 'my_post_type'],
'previous_text' => __( 'Vorige Pos' ),
'next_text' => __( 'Volgende Pos' ),
];
single_post_navigation( $args );
編集1
SOの投稿からのリクエストに応じて、の一部として@todo
、現在の投稿の投稿タイプからの投稿間だけでなく、ユーザーが設定した投稿タイプの配列からもナビゲートするサポートを導入しました。post_types
、関数のパラメーターました。更新されたコードをご覧ください。
編集2
引数に追加'suppress_filters' => true,
しWP_Query
て、ページネーションが内部で使用されるフィルターによって変更されないようにしますWP_Query