Question

wp_title( string $sep = '»',  bool $display = true,  string $seplocation = '' )

Display or retrieve page title for all areas of blog.

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description

By default, the page title will display the separator before the page title, so that the blog title will be before the page title. This is not good for title display, since the blog title shows up on most tabs and not what is important, which is the page that the user is looking at.

There are also SEO benefits to having the blog title after or to the ‘right’ of the page title. However, it is mostly common sense to have the blog title to the right with most browsers supporting tabs. You can achieve this by using the seplocation parameter and setting the value to ‘right’. This change was introduced around 2.5.0, in case backward compatibility of themes is important.

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参数

$sep

(string) (Optional) default is '»'. How to separate the various items within the page title.

Default value: '»'

$display

(bool) (Optional) Whether to display or retrieve title.

Default value: true

$seplocation

(string) (Optional) Direction to display title, 'right'.

Default value: ''

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返回值

(string|null) String on retrieve, null when displaying.

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源代码

File: wp-includes/general-template.php

function wp_title( $sep = '»', $display = true, $seplocation = '' ) {
	global $wp_locale;

	$m        = get_query_var( 'm' );
	$year     = get_query_var( 'year' );
	$monthnum = get_query_var( 'monthnum' );
	$day      = get_query_var( 'day' );
	$search   = get_query_var( 's' );
	$title    = '';

	$t_sep = '%WP_TITLE_SEP%'; // Temporary separator, for accurate flipping, if necessary

	// If there is a post
	if ( is_single() || ( is_home() && ! is_front_page() ) || ( is_page() && ! is_front_page() ) ) {
		$title = single_post_title( '', false );
	}

	// If there's a post type archive
	if ( is_post_type_archive() ) {
		$post_type = get_query_var( 'post_type' );
		if ( is_array( $post_type ) ) {
			$post_type = reset( $post_type );
		}
		$post_type_object = get_post_type_object( $post_type );
		if ( ! $post_type_object->has_archive ) {
			$title = post_type_archive_title( '', false );
		}
	}

	// If there's a category or tag
	if ( is_category() || is_tag() ) {
		$title = single_term_title( '', false );
	}

	// If there's a taxonomy
	if ( is_tax() ) {
		$term = get_queried_object();
		if ( $term ) {
			$tax   = get_taxonomy( $term->taxonomy );
			$title = single_term_title( $tax->labels->name . $t_sep, false );
		}
	}

	// If there's an author
	if ( is_author() && ! is_post_type_archive() ) {
		$author = get_queried_object();
		if ( $author ) {
			$title = $author->display_name;
		}
	}

	// Post type archives with has_archive should override terms.
	if ( is_post_type_archive() && $post_type_object->has_archive ) {
		$title = post_type_archive_title( '', false );
	}

	// If there's a month
	if ( is_archive() && ! empty( $m ) ) {
		$my_year  = substr( $m, 0, 4 );
		$my_month = $wp_locale->get_month( substr( $m, 4, 2 ) );
		$my_day   = intval( substr( $m, 6, 2 ) );
		$title    = $my_year . ( $my_month ? $t_sep . $my_month : '' ) . ( $my_day ? $t_sep . $my_day : '' );
	}

	// If there's a year
	if ( is_archive() && ! empty( $year ) ) {
		$title = $year;
		if ( ! empty( $monthnum ) ) {
			$title .= $t_sep . $wp_locale->get_month( $monthnum );
		}
		if ( ! empty( $day ) ) {
			$title .= $t_sep . zeroise( $day, 2 );
		}
	}

	// If it's a search
	if ( is_search() ) {
		/* translators: 1: separator, 2: search phrase */
		$title = sprintf( __( 'Search Results %1$s %2$s' ), $t_sep, strip_tags( $search ) );
	}

	// If it's a 404 page
	if ( is_404() ) {
		$title = __( 'Page not found' );
	}

	$prefix = '';
	if ( ! empty( $title ) ) {
		$prefix = " $sep ";
	}

	/**
	 * Filters the parts of the page title.
	 *
	 * @since 4.0.0
	 *
	 * @param array $title_array Parts of the page title.
	 */
	$title_array = apply_filters( 'wp_title_parts', explode( $t_sep, $title ) );

	// Determines position of the separator and direction of the breadcrumb
	if ( 'right' == $seplocation ) { // sep on right, so reverse the order
		$title_array = array_reverse( $title_array );
		$title       = implode( " $sep ", $title_array ) . $prefix;
	} else {
		$title = $prefix . implode( " $sep ", $title_array );
	}

	/**
	 * Filters the text of the page title.
	 *
	 * @since 2.0.0
	 *
	 * @param string $title Page title.
	 * @param string $sep Title separator.
	 * @param string $seplocation Location of the separator (left or right).
	 */
	$title = apply_filters( 'wp_title', $title, $sep, $seplocation );

	// Send it out
	if ( $display ) {
		echo $title;
	} else {
		return $title;
	}
}

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更新日志

Version	description
1.0.0	Introduced.

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More Information

Best practices

Plugins might use the wp_title filter to generate a value. While it is possible to construct a “title” by doing things such as concatenating with bloginfo (the Site Name), if you do not use the wp_title function in your theme, you will likely have errors or unexpected behavior.

Return Values

The function returns a concatenated string. It always queries the database for a default string; the value of the default string depends on the type of post or page:

Single post

the title of the post

Date-based archive 

the date (e.g., “2006”, “2006 – January”)

Category

the name of the category

Author page 

the public name of the user

The function then prepends or appends the sep string and returns the entire value.

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相关函数

Uses

• wp-includes/general-template.php: wp_title_parts
• wp-includes/l10n.php: __()
• wp-includes/formatting.php: zeroise()
• wp-includes/general-template.php: single_post_title()
• wp-includes/general-template.php: post_type_archive_title()
• wp-includes/general-template.php: single_term_title()
• wp-includes/general-template.php: wp_title
• wp-includes/query.php: is_single()
• wp-includes/query.php: is_search()
• wp-includes/query.php: is_404()
• wp-includes/query.php: is_home()
• wp-includes/query.php: is_front_page()
• wp-includes/query.php: is_page()
• wp-includes/query.php: is_category()
• wp-includes/query.php: is_tag()
• wp-includes/query.php: is_tax()
• wp-includes/query.php: is_author()
• wp-includes/query.php: get_query_var()
• wp-includes/query.php: is_post_type_archive()
• wp-includes/query.php: get_queried_object()
• wp-includes/query.php: is_archive()
• wp-includes/class-wp-locale.php: WP_Locale::get_month()
• wp-includes/taxonomy.php: get_taxonomy()
• wp-includes/plugin.php: apply_filters()
• wp-includes/post.php: get_post_type_object()
Show 20 more uses Hide more uses

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User Contributed Notes

1. Skip to note content You must log in to vote on the helpfulness of this noteVote results for this note: 6You must log in to vote on the helpfulness of this note Contributed by Dave Clements

   wp_title() was originally to be deprecated in 4.4, but was reinstated while efforts were made to identify the unintended ways in which the function was being used to ensure that the deprecation wouldn’t break them. With the likelihood that wp_title() will be deprecated in the near future, it is recommended that you instead use its replacement: the title-tag theme feature.

Customizing with the filter
If you want to change the way that the title displays on different pages you can use a filter.

/**
 * Filters wp_title to print a neat <title> tag based on what is being viewed.
 *
 * @param string $title Default title text for current view.
 * @param string $sep   Optional separator.
 * @return string The filtered title.
 */
function wpdocs_theme_name_wp_title( $title, $sep ) {
	if ( is_feed() ) {
		return $title;
	}
	
	global $page, $paged;

	// Add the blog name
	$title .= get_bloginfo( 'name', 'display' );

	// Add the blog description for the home/front page.
	$site_description = get_bloginfo( 'description', 'display' );
	if ( $site_description && ( is_home() || is_front_page() ) ) {
		$title .= " $sep $site_description";
	}

	// Add a page number if necessary:
	if ( ( $paged >= 2 || $page >= 2 ) && ! is_404() ) {
		$title .= " $sep " . sprintf( __( 'Page %s', '_s' ), max( $paged, $page ) );
	}
	return $title;
}
add_filter( 'wp_title', 'wpdocs_theme_name_wp_title', 10, 2 );

Zero-character sep
The sep string may be zero characters, which will remove » from the returned value. To do this, set the sep parameter to zero characters, for example:

<title><?php wp_title(''); ?></title>

If the title of the post is “Hello world!”, then the function will return:

Hello world!

Following is the recommended way instead of wp_title() function.

/*
 * Let WordPress manage the document title.
 * By adding theme support, we declare that this theme does not use a
 * hard-coded <title> tag in the document head, and expect WordPress to
 * provide it for us.
 */
add_theme_support( 'title-tag' );;

It should be placed in the functions.php file with after_setup_theme action hook.

Default
If you do not pass any parameters for a single post, for example:

<title><?php wp_title(); ?></title>

If the title of the post is “Hello world!”, then the function will return

» Hello world!

Covering Homepage
If you are using a custom homepage with custom loops and stuff or a custom front-page, you will have an empty wp_title. Here goes a neat hack to add the description/tagline at the wp_title place on homepage:

<title><?php wp_title(''); ?></title>

Then in your functions.php file in your theme:

add_filter( 'wp_title', 'wpdocs_hack_wp_title_for_home' );

/**
 * Customize the title for the home page, if one is not set.
 *
 * @param string $title The original title.
 * @return string The title to use.
 */
function wpdocs_hack_wp_title_for_home( $title )
{
  if ( empty( $title ) && ( is_home() || is_front_page() ) ) {
    $title = __( 'Home', 'textdomain' ) . ' | ' . get_bloginfo( 'description' );
  }
  return $title;
}

You can format this string as you want of course.

Just wanted to check line 833 for mis-spelling:

$t_sep = ‘%WP_TITILE_SEP%’; // Temporary separator, for accurate flipping, if necessary

Is WP_TITILE_SEP spelled correctly? I might have thought it to be WP_TITLE_SEP

I noticed this in my WP php file, and then again here.

Display blog title after page/post title:

<title><?php wp_title(''); echo ' | ';  bloginfo( 'name' ); ?></title>