get_calendar( bool $initial = true, bool $display = true ): void|string

Displays calendar with days that have posts as links.

Description

The calendar is cached, which will be retrieved, if it exists. If there are no posts for the month, then it will not be displayed.

Parameters

$initialbooloptional
Whether to use initial calendar names.

Default:true

$displaybooloptional
Whether to display the calendar output.

Default:true

Return

void|string Void if $display argument is true, calendar HTML if $display is false.

Source

function get_calendar( $initial = true, $display = true ) {
	global $wpdb, $m, $monthnum, $year, $wp_locale, $posts;

	$key   = md5( $m . $monthnum . $year );
	$cache = wp_cache_get( 'get_calendar', 'calendar' );

	if ( $cache && is_array( $cache ) && isset( $cache[ $key ] ) ) {
		/** This filter is documented in wp-includes/general-template.php */
		$output = apply_filters( 'get_calendar', $cache[ $key ] );

		if ( $display ) {
			echo $output;
			return;
		}

		return $output;
	}

	if ( ! is_array( $cache ) ) {
		$cache = array();
	}

	// Quick check. If we have no posts at all, abort!
	if ( ! $posts ) {
		$gotsome = $wpdb->get_var( "SELECT 1 as test FROM $wpdb->posts WHERE post_type = 'post' AND post_status = 'publish' LIMIT 1" );
		if ( ! $gotsome ) {
			$cache[ $key ] = '';
			wp_cache_set( 'get_calendar', $cache, 'calendar' );
			return;
		}
	}

	if ( isset( $_GET['w'] ) ) {
		$w = (int) $_GET['w'];
	}
	// week_begins = 0 stands for Sunday.
	$week_begins = (int) get_option( 'start_of_week' );

	// Let's figure out when we are.
	if ( ! empty( $monthnum ) && ! empty( $year ) ) {
		$thismonth = zeroise( (int) $monthnum, 2 );
		$thisyear  = (int) $year;
	} elseif ( ! empty( $w ) ) {
		// We need to get the month from MySQL.
		$thisyear = (int) substr( $m, 0, 4 );
		// It seems MySQL's weeks disagree with PHP's.
		$d         = ( ( $w - 1 ) * 7 ) + 6;
		$thismonth = $wpdb->get_var( "SELECT DATE_FORMAT((DATE_ADD('{$thisyear}0101', INTERVAL $d DAY) ), '%m')" );
	} elseif ( ! empty( $m ) ) {
		$thisyear = (int) substr( $m, 0, 4 );
		if ( strlen( $m ) < 6 ) {
			$thismonth = '01';
		} else {
			$thismonth = zeroise( (int) substr( $m, 4, 2 ), 2 );
		}
	} else {
		$thisyear  = current_time( 'Y' );
		$thismonth = current_time( 'm' );
	}

	$unixmonth = mktime( 0, 0, 0, $thismonth, 1, $thisyear );
	$last_day  = gmdate( 't', $unixmonth );

	// Get the next and previous month and year with at least one post.
	$previous = $wpdb->get_row(
		"SELECT MONTH(post_date) AS month, YEAR(post_date) AS year
		FROM $wpdb->posts
		WHERE post_date < '$thisyear-$thismonth-01'
		AND post_type = 'post' AND post_status = 'publish'
		ORDER BY post_date DESC
		LIMIT 1"
	);
	$next     = $wpdb->get_row(
		"SELECT MONTH(post_date) AS month, YEAR(post_date) AS year
		FROM $wpdb->posts
		WHERE post_date > '$thisyear-$thismonth-{$last_day} 23:59:59'
		AND post_type = 'post' AND post_status = 'publish'
		ORDER BY post_date ASC
		LIMIT 1"
	);

	/* translators: Calendar caption: 1: Month name, 2: 4-digit year. */
	$calendar_caption = _x( '%1$s %2$s', 'calendar caption' );
	$calendar_output  = '<table id="wp-calendar" class="wp-calendar-table">
	<caption>' . sprintf(
		$calendar_caption,
		$wp_locale->get_month( $thismonth ),
		gmdate( 'Y', $unixmonth )
	) . '</caption>
	<thead>
	<tr>';

	$myweek = array();

	for ( $wdcount = 0; $wdcount <= 6; $wdcount++ ) {
		$myweek[] = $wp_locale->get_weekday( ( $wdcount + $week_begins ) % 7 );
	}

	foreach ( $myweek as $wd ) {
		$day_name         = $initial ? $wp_locale->get_weekday_initial( $wd ) : $wp_locale->get_weekday_abbrev( $wd );
		$wd               = esc_attr( $wd );
		$calendar_output .= "\n\t\t<th scope=\"col\" title=\"$wd\">$day_name</th>";
	}

	$calendar_output .= '
	</tr>
	</thead>
	<tbody>
	<tr>';

	$daywithpost = array();

	// Get days with posts.
	$dayswithposts = $wpdb->get_results(
		"SELECT DISTINCT DAYOFMONTH(post_date)
		FROM $wpdb->posts WHERE post_date >= '{$thisyear}-{$thismonth}-01 00:00:00'
		AND post_type = 'post' AND post_status = 'publish'
		AND post_date <= '{$thisyear}-{$thismonth}-{$last_day} 23:59:59'",
		ARRAY_N
	);

	if ( $dayswithposts ) {
		foreach ( (array) $dayswithposts as $daywith ) {
			$daywithpost[] = (int) $daywith[0];
		}
	}

	// See how much we should pad in the beginning.
	$pad = calendar_week_mod( gmdate( 'w', $unixmonth ) - $week_begins );
	if ( 0 != $pad ) {
		$calendar_output .= "\n\t\t" . '<td colspan="' . esc_attr( $pad ) . '" class="pad">&nbsp;</td>';
	}

	$newrow      = false;
	$daysinmonth = (int) gmdate( 't', $unixmonth );

	for ( $day = 1; $day <= $daysinmonth; ++$day ) {
		if ( isset( $newrow ) && $newrow ) {
			$calendar_output .= "\n\t</tr>\n\t<tr>\n\t\t";
		}
		$newrow = false;

		if ( current_time( 'j' ) == $day &&
			current_time( 'm' ) == $thismonth &&
			current_time( 'Y' ) == $thisyear ) {
			$calendar_output .= '<td id="today">';
		} else {
			$calendar_output .= '<td>';
		}

		if ( in_array( $day, $daywithpost, true ) ) {
			// Any posts today?
			$date_format = gmdate( _x( 'F j, Y', 'daily archives date format' ), strtotime( "{$thisyear}-{$thismonth}-{$day}" ) );
			/* translators: Post calendar label. %s: Date. */
			$label            = sprintf( __( 'Posts published on %s' ), $date_format );
			$calendar_output .= sprintf(
				'<a href="%s" aria-label="%s">%s</a>',
				get_day_link( $thisyear, $thismonth, $day ),
				esc_attr( $label ),
				$day
			);
		} else {
			$calendar_output .= $day;
		}

		$calendar_output .= '</td>';

		if ( 6 == calendar_week_mod( gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins ) ) {
			$newrow = true;
		}
	}

	$pad = 7 - calendar_week_mod( gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins );
	if ( 0 != $pad && 7 != $pad ) {
		$calendar_output .= "\n\t\t" . '<td class="pad" colspan="' . esc_attr( $pad ) . '">&nbsp;</td>';
	}

	$calendar_output .= "\n\t</tr>\n\t</tbody>";

	$calendar_output .= "\n\t</table>";

	$calendar_output .= '<nav aria-label="' . __( 'Previous and next months' ) . '" class="wp-calendar-nav">';

	if ( $previous ) {
		$calendar_output .= "\n\t\t" . '<span class="wp-calendar-nav-prev"><a href="' . get_month_link( $previous->year, $previous->month ) . '">&laquo; ' .
			$wp_locale->get_month_abbrev( $wp_locale->get_month( $previous->month ) ) .
		'</a></span>';
	} else {
		$calendar_output .= "\n\t\t" . '<span class="wp-calendar-nav-prev">&nbsp;</span>';
	}

	$calendar_output .= "\n\t\t" . '<span class="pad">&nbsp;</span>';

	if ( $next ) {
		$calendar_output .= "\n\t\t" . '<span class="wp-calendar-nav-next"><a href="' . get_month_link( $next->year, $next->month ) . '">' .
			$wp_locale->get_month_abbrev( $wp_locale->get_month( $next->month ) ) .
		' &raquo;</a></span>';
	} else {
		$calendar_output .= "\n\t\t" . '<span class="wp-calendar-nav-next">&nbsp;</span>';
	}

	$calendar_output .= '
	</nav>';

	$cache[ $key ] = $calendar_output;
	wp_cache_set( 'get_calendar', $cache, 'calendar' );

	if ( $display ) {
		/**
		 * Filters the HTML calendar output.
		 *
		 * @since 3.0.0
		 *
		 * @param string $calendar_output HTML output of the calendar.
		 */
		echo apply_filters( 'get_calendar', $calendar_output );
		return;
	}
	/** This filter is documented in wp-includes/general-template.php */
	return apply_filters( 'get_calendar', $calendar_output );
}

Hooks

apply_filters( ‘get_calendar’, string $calendar_output )

Filters the HTML calendar output.

Changelog

VersionDescription
1.0.0Introduced.

User Contributed Notes

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