the_date()　WordPress関数　テンプレートタグ

<?php
/**
2330	 * Display or Retrieve the date the current post was written (once per date)
2331	 *
2332	 * Will only output the date if the current post's date is different from the
2333	 * previous one output.
2334	 *
2335	 * i.e. Only one date listing will show per day worth of posts shown in the loop, even if the
2336	 * function is called several times for each post.
2337	 *
2338	 * HTML output can be filtered with 'the_date'.
2339	 * Date string output can be filtered with 'get_the_date'.
2340	 *
2341	 * @since 0.71
2342	 *
2343	 * @global string $currentday  The day of the current post in the loop.
2344	 * @global string $previousday The day of the previous post in the loop.
2345	 *
2346	 * @param string $d      Optional. PHP date format defaults to the date_format option if not specified.
2347	 * @param string $before Optional. Output before the date.
2348	 * @param string $after  Optional. Output after the date.
2349	 * @param bool   $echo   Optional, default is display. Whether to echo the date or return it.
2350	 * @return string|void String if retrieving.
2351	 */
2352	function the_date( $d = '', $before = '', $after = '', $echo = true ) {
2353	        global $currentday, $previousday;
2354	
2355	        $the_date = '';
2356	
2357	        if ( is_new_day() ) {
2358	                $the_date    = $before . get_the_date( $d ) . $after;
2359	                $previousday = $currentday;
2360	        }
2361	
2362	        /**
2363	         * Filters the date a post was published for display.
2364	         *
2365	         * @since 0.71
2366	         *
2367	         * @param string $the_date The formatted date string.
2368	         * @param string $d        PHP date format. Defaults to 'date_format' option
2369	         *                         if not specified.
2370	         * @param string $before   HTML output before the date.
2371	         * @param string $after    HTML output after the date.
2372	         */
2373	        $the_date = apply_filters( 'the_date', $the_date, $d, $before, $after );
2374	
2375	        if ( $echo ) {
2376	                echo $the_date;
2377	        } else {
2378	                return $the_date;
2379	        }
2380	}
2381	
2382	/**
2383	 * Retrieve the date on which the post was written.
2384	 *
2385	 * Unlike the_date() this function will always return the date.
2386	 * Modify output with the {@see 'get_the_date'} filter.
2387	 *
2388	 * @since 3.0.0
2389	 *
2390	 * @param  string      $d    Optional. PHP date format defaults to the date_format option if not specified.
2391	 * @param  int|WP_Post $post Optional. Post ID or WP_Post object. Default current post.
2392	 * @return false|string Date the current post was written. False on failure.
2393	 */
2394	function get_the_date( $d = '', $post = null ) {
2395	        $post = get_post( $post );
2396	
2397	        if ( ! $post ) {
2398	                return false;
2399	        }
2400	
2401	        if ( '' == $d ) {
2402	                $the_date = get_post_time( get_option( 'date_format' ), false, $post, true );
2403	        } else {
2404	                $the_date = get_post_time( $d, false, $post, true );
2405	        }
2406	
2407	        /**
2408	         * Filters the date a post was published.
2409	         *
2410	         * @since 3.0.0
2411	         *
2412	         * @param string      $the_date The formatted date.
2413	         * @param string      $d        PHP date format. Defaults to 'date_format' option
2414	         *                              if not specified.
2415	         * @param int|WP_Post $post     The post object or ID.
2416	         */
2417	        return apply_filters( 'get_the_date', $the_date, $d, $post );
2418	}
?>