WordPress函数：wp_get_archives
一、函数简介
根据类型和格式显示存档链接。（Displays archive links based on type and format.）
二、函数参数
* @return void|string Void if 'echo' argument is true, archive links if 'echo' is false.
三、函数案例
<?php wp_get_archives( $args = '' ) ?>
四、源代码
/**
* Displays archive links based on type and format.
*
* @since 1.2.0
* @since 4.4.0 The `$post_type` argument was added.
* @since 5.2.0 The `$year`, `$monthnum`, `$day`, and `$w` arguments were added.
*
* @see get_archives_link()
*
* @global wpdb $wpdb WordPress database abstraction object.
* @global WP_Locale $wp_locale WordPress date and time locale object.
*
* @param string|array $args {
* Default archive links arguments. Optional.
*
* @type string $type Type of archive to retrieve. Accepts 'daily', 'weekly', 'monthly',
* 'yearly', 'postbypost', or 'alpha'. Both 'postbypost' and 'alpha'
* display the same archive link list as well as post titles instead
* of displaying dates. The difference between the two is that 'alpha'
* will order by post title and 'postbypost' will order by post date.
* Default 'monthly'.
* @type string|int $limit Number of links to limit the query to. Default empty (no limit).
* @type string $format Format each link should take using the $before and $after args.
* Accepts 'link' (`<link>` tag), 'option' (`<option>` tag), 'html'
* (`<li>` tag), or a custom format, which generates a link anchor
* with $before preceding and $after succeeding. Default 'html'.
* @type string $before Markup to prepend to the beginning of each link. Default empty.
* @type string $after Markup to append to the end of each link. Default empty.
* @type bool $show_post_count Whether to display the post count alongside the link. Default false.
* @type bool|int $echo Whether to echo or return the links list. Default 1|true to echo.
* @type string $order Whether to use ascending or descending order. Accepts 'ASC', or 'DESC'.
* Default 'DESC'.
* @type string $post_type Post type. Default 'post'.
* @type string $year Year. Default current year.
* @type string $monthnum Month number. Default current month number.
* @type string $day Day. Default current day.
* @type string $w Week. Default current week.
* }
* @return void|string Void if 'echo' argument is true, archive links if 'echo' is false.
*/
function wp_get_archives( $args = '' ) {
global $wpdb, $wp_locale;
$defaults = array(
'type' => 'monthly',
'limit' => '',
'format' => 'html',
'before' => '',
'after' => '',
'show_post_count' => false,
'echo' => 1,
'order' => 'DESC',
'post_type' => 'post',
'year' => get_query_var( 'year' ),
'monthnum' => get_query_var( 'monthnum' ),
'day' => get_query_var( 'day' ),
'w' => get_query_var( 'w' ),
);
$parsed_args = wp_parse_args( $args, $defaults );
$post_type_object = get_post_type_object( $parsed_args['post_type'] );
if ( ! is_post_type_viewable( $post_type_object ) ) {
return;
}
$parsed_args['post_type'] = $post_type_object->name;
if ( '' === $parsed_args['type'] ) {
$parsed_args['type'] = 'monthly';
}
if ( ! empty( $parsed_args['limit'] ) ) {
$parsed_args['limit'] = absint( $parsed_args['limit'] );
$parsed_args['limit'] = ' LIMIT ' . $parsed_args['limit'];
}
$order = strtoupper( $parsed_args['order'] );
if ( 'ASC' !== $order ) {
$order = 'DESC';
}
// This is what will separate dates on weekly archive links.
$archive_week_separator = '–';
$sql_where = $wpdb->prepare( "WHERE post_type = %s AND post_status = 'publish'", $parsed_args['post_type'] );
/**
* Filters the SQL WHERE clause for retrieving archives.
*
* @since 2.2.0
*
* @param string $sql_where Portion of SQL query containing the WHERE clause.
* @param array $parsed_args An array of default arguments.
*/
$where = apply_filters( 'getarchives_where', $sql_where, $parsed_args );
/**
* Filters the SQL JOIN clause for retrieving archives.
*
* @since 2.2.0
*
* @param string $sql_join Portion of SQL query containing JOIN clause.
* @param array $parsed_args An array of default arguments.
*/
$join = apply_filters( 'getarchives_join', '', $parsed_args );
$output = '';
$last_changed = wp_cache_get_last_changed( 'posts' );
$limit = $parsed_args['limit'];
if ( 'monthly' === $parsed_args['type'] ) {
$query = "SELECT YEAR(post_date) AS `year`, MONTH(post_date) AS `month`, count(ID) as posts FROM $wpdb->posts $join $where GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date $order $limit";
$key = md5( $query );
$key = "wp_get_archives:$key";
$results = wp_cache_get_salted( $key, 'post-queries', $last_changed );
if ( ! $results ) {
$results = $wpdb->get_results( $query );
wp_cache_set_salted( $key, $results, 'post-queries', $last_changed );
}
if ( $results ) {
$after = $parsed_args['after'];
foreach ( (array) $results as $result ) {
$url = get_month_link( $result->year, $result->month );
if ( 'post' !== $parsed_args['post_type'] ) {
$url = add_query_arg( 'post_type', $parsed_args['post_type'], $url );
}
/* translators: 1: Month name, 2: 4-digit year. */
$text = sprintf( __( '%1$s %2$d' ), $wp_locale->get_month( $result->month ), $result->year );
if ( $parsed_args['show_post_count'] ) {
$parsed_args['after'] = ' (' . $result->posts . ')' . $after;
}
$selected = is_archive() && (string) $parsed_args['year'] === $result->year && (string) $parsed_args['monthnum'] === $result->month;
$output .= get_archives_link( $url, $text, $parsed_args['format'], $parsed_args['before'], $parsed_args['after'], $selected );
}
}
} elseif ( 'yearly' === $parsed_args['type'] ) {
$query = "SELECT YEAR(post_date) AS `year`, count(ID) as posts FROM $wpdb->posts $join $where GROUP BY YEAR(post_date) ORDER BY post_date $order $limit";
$key = md5( $query );
$key = "wp_get_archives:$key";
$results = wp_cache_get_salted( $key, 'post-queries', $last_changed );
if ( ! $results ) {
$results = $wpdb->get_results( $query );
wp_cache_set_salted( $key, $results, 'post-queries', $last_changed );
}
if ( $results ) {
$after = $parsed_args['after'];
foreach ( (array) $results as $result ) {
$url = get_year_link( $result->year );
if ( 'post' !== $parsed_args['post_type'] ) {
$url = add_query_arg( 'post_type', $parsed_args['post_type'], $url );
}
$text = sprintf( '%d', $result->year );
if ( $parsed_args['show_post_count'] ) {
$parsed_args['after'] = ' (' . $result->posts . ')' . $after;
}
$selected = is_archive() && (string) $parsed_args['year'] === $result->year;
$output .= get_archives_link( $url, $text, $parsed_args['format'], $parsed_args['before'], $parsed_args['after'], $selected );
}
}
} elseif ( 'daily' === $parsed_args['type'] ) {
$query = "SELECT YEAR(post_date) AS `year`, MONTH(post_date) AS `month`, DAYOFMONTH(post_date) AS `dayofmonth`, count(ID) as posts FROM $wpdb->posts $join $where GROUP BY YEAR(post_date), MONTH(post_date), DAYOFMONTH(post_date) ORDER BY post_date $order $limit";
$key = md5( $query );
$key = "wp_get_archives:$key";
$results = wp_cache_get_salted( $key, 'post-queries', $last_changed );
if ( ! $results ) {
$results = $wpdb->get_results( $query );
wp_cache_set_salted( $key, $results, 'post-queries', $last_changed );
}
if ( $results ) {
$after = $parsed_args['after'];
foreach ( (array) $results as $result ) {
$url = get_day_link( $result->year, $result->month, $result->dayofmonth );
if ( 'post' !== $parsed_args['post_type'] ) {
$url = add_query_arg( 'post_type', $parsed_args['post_type'], $url );
}
$date = sprintf( '%1$d-%2$02d-%3$02d 00:00:00', $result->year, $result->month, $result->dayofmonth );
$text = mysql2date( get_option( 'date_format' ), $date );
if ( $parsed_args['show_post_count'] ) {
$parsed_args['after'] = ' (' . $result->posts . ')' . $after;
}
$selected = is_archive() && (string) $parsed_args['year'] === $result->year && (string) $parsed_args['monthnum'] === $result->month && (string) $parsed_args['day'] === $result->dayofmonth;
$output .= get_archives_link( $url, $text, $parsed_args['format'], $parsed_args['before'], $parsed_args['after'], $selected );
}
}
} elseif ( 'weekly' === $parsed_args['type'] ) {
$week = _wp_mysql_week( '`post_date`' );
$query = "SELECT DISTINCT $week AS `week`, YEAR( `post_date` ) AS `yr`, DATE_FORMAT( `post_date`, '%Y-%m-%d' ) AS `yyyymmdd`, count( `ID` ) AS `posts` FROM `$wpdb->posts` $join $where GROUP BY $week, YEAR( `post_date` ) ORDER BY `post_date` $order $limit";
$key = md5( $query );
$key = "wp_get_archives:$key";
$results = wp_cache_get_salted( $key, 'post-queries', $last_changed );
if ( ! $results ) {
$results = $wpdb->get_results( $query );
wp_cache_set_salted( $key, $results, 'post-queries', $last_changed );
}
$arc_w_last = '';
if ( $results ) {
$after = $parsed_args['after'];
foreach ( (array) $results as $result ) {
if ( $result->week !== $arc_w_last ) {
$arc_year = $result->yr;
$arc_w_last = $result->week;
$arc_week = get_weekstartend( $result->yyyymmdd, get_option( 'start_of_week' ) );
$arc_week_start = date_i18n( get_option( 'date_format' ), $arc_week['start'] );
$arc_week_end = date_i18n( get_option( 'date_format' ), $arc_week['end'] );
$url = add_query_arg(
array(
'm' => $arc_year,
'w' => $result->week,
),
home_url( '/' )
);
if ( 'post' !== $parsed_args['post_type'] ) {
$url = add_query_arg( 'post_type', $parsed_args['post_type'], $url );
}
$text = $arc_week_start . $archive_week_separator . $arc_week_end;
if ( $parsed_args['show_post_count'] ) {
$parsed_args['after'] = ' (' . $result->posts . ')' . $after;
}
$selected = is_archive() && (string) $parsed_args['year'] === $result->yr && (string) $parsed_args['w'] === $result->week;
$output .= get_archives_link( $url, $text, $parsed_args['format'], $parsed_args['before'], $parsed_args['after'], $selected );
}
}
}
} elseif ( ( 'postbypost' === $parsed_args['type'] ) || ( 'alpha' === $parsed_args['type'] ) ) {
$orderby = ( 'alpha' === $parsed_args['type'] ) ? 'post_title ASC ' : 'post_date DESC, ID DESC ';
$query = "SELECT * FROM $wpdb->posts $join $where ORDER BY $orderby $limit";
$key = md5( $query );
$key = "wp_get_archives:$key";
$results = wp_cache_get_salted( $key, 'post-queries', $last_changed );
if ( ! $results ) {
$results = $wpdb->get_results( $query );
wp_cache_set_salted( $key, $results, 'post-queries', $last_changed );
}
if ( $results ) {
foreach ( (array) $results as $result ) {
if ( '0000-00-00 00:00:00' !== $result->post_date ) {
$url = get_permalink( $result );
if ( $result->post_title ) {
/** This filter is documented in wp-includes/post-template.php */
$text = strip_tags( apply_filters( 'the_title', $result->post_title, $result->ID ) );
} else {
$text = $result->ID;
}
$selected = get_the_ID() === $result->ID;
$output .= get_archives_link( $url, $text, $parsed_args['format'], $parsed_args['before'], $parsed_args['after'], $selected );
}
}
}
}
if ( $parsed_args['echo'] ) {
echo $output;
} else {
return $output;
}
}
THE END
