```
/**
* Theme Name: My theme (required)
* Template: The name of the parent theme. E.g. Twenty Seventeen
* Description: A short description of the theme.
*
* Theme URI: Subject URL. E.g. http://wordpress.org/themes/twenty
* Author: Kama
* Author URI: https://wp-kama.com
*
* Tags: black, brown, orange
* Text Domain: Subject translation domain. E.g. twentythirteen
*
* License: License. E.g. GNU General Public License v2 or later
* License URI: http://www.gnu.org/licenses/gpl-2.0.html
*
* Version: 1.0
*/
```
## .htaccess code
```
# BEGIN WordPress
# The directives (lines) between "BEGIN WordPress" and "END WordPress" are
# dynamically generated, and should only be modified via WordPress filters.
# Any changes to the directives between these markers will be overwritten.
RewriteEngine On
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
# END WordPress
```
[Theme files include functions](https://wp-kama.com/function-cat/theme-files)- *<?php get\_header(); ?>header.php.*
- *<?php get\_template\_part('file'); ?>file.php.*
- *<?php get\_search\_form(); ?>Search form searchform.php.*
- *<?php comments\_template(); ?>Comments form comments.php.*
- *<?php get\_sidebar(); ?>sidebar.php.*
- *<?php get\_footer(); ?>footer.php.*
-
- *[get\_template\_directory()](https://wp-kama.com/function/get_template_directory "$tpl_dir = get_template_directory();
")The path to the parent theme (not child). No trailing /.*
- *[get\_stylesheet\_directory()](https://wp-kama.com/function/get_stylesheet_directory "get_stylesheet_directory();
")Theme Path (where parent/child style.css). No trailing /.*
- *[get\_parent\_theme\_file\_path()](https://wp-kama.com/function/get_parent_theme_file_path "get_parent_theme_file_path( $file = '' );
")File path of parent theme (not child).*
- *[get\_theme\_file\_path()](https://wp-kama.com/function/get_theme_file_path "$filepath = get_theme_file_path( $file );
")File path of parent/child theme.*
- *[load\_template()](https://wp-kama.com/function/load_template "load_template( $_template_file, $require_once, $args );
")Includes file (require\_once).*
- *[locate\_template()](https://wp-kama.com/function/locate_template "locate_template( $template_names, $load, $require_once, $args );
")Finds/Includes parent/child theme file.*
-
- *[get\_template\_directory\_uri()](https://wp-kama.com/function/get_template_directory_uri)URL of parent theme (not child). No trailing /.*
- *[get\_stylesheet\_directory\_uri()](https://wp-kama.com/function/get_stylesheet_directory_uri "$theme_url = get_stylesheet_directory_uri();
")Theme URL (child theme if it exists). No trailing /.*
- *[get\_theme\_root\_uri()](https://wp-kama.com/function/get_theme_root_uri "get_theme_root_uri( $stylesheet_or_template, $theme_root );
")URL of the theme's DIR. No trailing /.*
- *[get\_stylesheet\_uri()](https://wp-kama.com/function/get_stylesheet_uri)URL of the theme's style.css file.*
- *[get\_theme\_file\_uri()](https://wp-kama.com/function/get_theme_file_uri "get_theme_file_uri( $file );
")URL of the parent/child theme file.*
- *[get\_parent\_theme\_file\_uri()](https://wp-kama.com/function/get_parent_theme_file_uri "get_parent_theme_file_uri( $file );
")URL of the parent theme file.*
## Theme Files `(hierarchy)` `/themes/THEME/`
[Theme Files Hierarchy](https://wp-kama.com/67/theme-files-hierarchy)- *style*.css*Theme styles file (required)*
- *index*.php*Any page without a template file (required)*
- *front-page*.php*Front (Home) page*
- *home*.php*Posts page (or Home page)*
- *functions*.php*A special file for php functions (code)*
- *404*.php*Page **"not found"***
- *comments*.php***Comments** Template (part)*
- *header*.php***Site Header** Template (part)*
- *searchform*.php***Search Form** Template (part)*
- *sidebar*.php***Sidebar** Template (part)*
- *footer*.php***Site Footer** Template (part)*
- *single*.php*Post page **post\_type = post***
- *single-POST\_TYPE*.php*Post page **post\_type = POST\_TYPE***
- *single-POST\_TYPE-POST\_NAME*.php*Post page with **POST\_NAME and POST\_TYPE***
- *singular*.php*Post of **any post type***
- *page*.php*Page **post\_type = page***
- *page-POST\_NAME*.php*Page **post\_name = POST\_NAME***
- *page-ID*.php*Page **ID = ID***
- *attachment*.php*Any **attachment** page*
- *image*.php*Image **attachment** page*
- *archive*.php*Page of **any archive***
- *archive-POST\_TYPE*.php*Page of **post type archive***
- *search*.php***Search** page*
- *category*.php*Any **Category** page*
- *category-SLUG*.php*Category page with **slug = SLUG***
- *category-ID*.php*Category page with **term\_id = id***
- *tag*.php*Any **Tag** page*
- *tag-SLUG*.php*Tag page with **slug = SLUG***
- *tag-ID*.php*Tag page with **term\_id = id***
- *taxonomy*.php*Any **custom taxonomy element** page*
- *taxonomy-TAXONOMY*.php*Page of any term of TAXONOMY taxonomy*
- *taxonomy-TAXONOMY-SLUG*.php*Page of SLUG term of TAXONOMY taxonomy*
- *author*.php*Page of **Author posts***
A post template from any file:
```
[Read more about post templates](https://wp-kama.com/63/page-template-for-any-post-type-in-wp-4-7)
## Site Information `bloginfo`
- *[bloginfo()](https://wp-kama.com/function/bloginfo "bloginfo( $show );
")Displays **information about the site**.*
- *[get\_bloginfo()](https://wp-kama.com/function/get_bloginfo "get_bloginfo( $show, $filter );
")Gets **information about the site**.*
-
- *<?php bloginfo('name'); ?>Site name.*
- *<?php bloginfo('description'); ?>Short description of the site.*
- *<?php bloginfo('template\_url'); ?>Theme URL: [get\_template\_directory()](https://wp-kama.com/function/get_template_directory).*
- *<?php bloginfo('template\_directory'); ?>Same as template\_url.*
- *<?php bloginfo('stylesheet\_directory'); ?>Theme URL: [get\_stylesheet\_directory\_uri()](https://wp-kama.com/function/get_stylesheet_directory_uri).*
- *<?php bloginfo('stylesheet\_url'); ?>Theme file style.css URL: [get\_stylesheet\_uri()](https://wp-kama.com/function/get_stylesheet_uri).*
- *<?php bloginfo('charset'); ?>The site's encoding: UTF-8.*
- *<?php bloginfo('html\_type'); ?>Content-Type of the page: text/html.*
- *<?php bloginfo('language'); ?>Site locale (language): RU.*
- *<?php bloginfo('version'); ?>WordPress version: 5.5.3.*
- *<?php bloginfo('rss2\_url '); ?>URL of the feed: /feed.*
- *<?php bloginfo('comments\_rss2\_url'); ?>URL of the comments feed: /comments/feed.*
- *<?php bloginfo('admin\_email'); ?>E-mail of Admin.*
-
- *<?php bloginfo('pingback\_url'); ?>Notification URL to the xmlrpc.php file.*
- *<?php bloginfo('rdf\_url'); ?>RDF/RSS 1.0 feed URL (/feed/rfd).*
- *<?php bloginfo('rss\_url'); ?>RSS 0.92 feed URL (/feed/rss).*
- *<?php bloginfo('atom\_url '); ?>Atom feed URL (/feed/atom).*
- *<?php bloginfo('url'); ?>Home page URL. Alias [home\_url()](https://wp-kama.com/function/home_url).*
- *<?php bloginfo('wpurl'); ?>Admin panel URL. Alias [site\_url()](https://wp-kama.com/function/site_url).*
## Comment Loop
- *[comment\_ID()](https://wp-kama.com/function/comment_ID "
")Displays the ID of the current comment.*
- *[comments\_popup\_link()](https://wp-kama.com/function/comments_popup_link "comments_popup_link( $zero, $one, $more, $css_class, $none);
")Displays <a> link to the comment popup.*
- *[comment\_text()](https://wp-kama.com/function/comment_text "
")Displays the text of the comment.*
- *[comment\_author()](https://wp-kama.com/function/comment_author "
")Displays the comment author name.*
- *[comments\_link()](https://wp-kama.com/function/comments_link "
")Displays a URL to the post comment form.*
- *[comment\_reply\_link()](https://wp-kama.com/function/comment_reply_link "
")Displays a <a> link that allows you to reply to comments.*
- *[comment\_time()](https://wp-kama.com/function/comment_time "comment_time( $d );
")Displays the comment publishing time.*
- *[comment\_author\_link()](https://wp-kama.com/function/comment_author_link "
")Displays the comment author's name as a link.*
- *[comment\_author\_url()](https://wp-kama.com/function/comment_author_url "
")Displays comment author URL (sets when commenting).*
- *[comment\_author\_url\_link()](https://wp-kama.com/function/comment_author_url_link "
")Displays comment author link (A tag).*
- *[comment\_author\_email\_link()](https://wp-kama.com/function/comment_author_email_link)Displays comment author email as a mailto link.*
- *[edit\_comment\_link()](https://wp-kama.com/function/edit_comment_link "
")Displays edit comment link.*
## The Loop
[The Loop](https://wp-kama.com/1572/the-loop)[3 ways to Create Loop in WordPress](https://wp-kama.com/1573/3-ways-to-create-loop)- *[in\_the\_loop()](https://wp-kama.com/function/in_the_loop "if( in_the_loop() ){
// we inside the loop...
}
")Checks if the WordPress loop is active.*
- *[have\_posts()](https://wp-kama.com/function/have_posts "// not loop
if( have_posts() ){
// ...
} // loop
while ( have_posts() ) {
the_post(); // ...
}
")Checks if there are posts for the loop.*
- *[the\_post()](https://wp-kama.com/function/the_post)Sets the next post in the loop and global $post.*
- *[setup\_postdata()](https://wp-kama.com/function/setup_postdata "global $post;
setup_postdata( $post );
")Sets global $post.*
- *[the\_ID()](https://wp-kama.com/function/the_ID "
")Displays the ID of the current post.*
- *[the\_title()](https://wp-kama.com/function/the_title "the_title( $before, $after, $echo );
")Displays current post title.*
- *[the\_title\_attribute()](https://wp-kama.com/function/the_title_attribute)Displays post title for html tag attribute.*
- *[the\_content()](https://wp-kama.com/function/the_content "
")Displays post content.*
- *[the\_excerpt()](https://wp-kama.com/function/the_excerpt "
")Displays the excerpt (quote) of the post, with \[...\] at the end.*
- *[the\_excerpt\_rss()](https://wp-kama.com/function/the_excerpt_rss "
")Displays the excerpt (quote) (for RSS).*
- *[get\_permalink()](https://wp-kama.com/function/get_permalink "$url = get_permalink( $post, $leavename );
")Gets post URL.*
- *[the\_permalink()](https://wp-kama.com/function/the_permalink)Displays post URL.*
- *[comments\_number()](https://wp-kama.com/function/comments_number "
")Displays post's number of comments.*
- *[edit\_post\_link()](https://wp-kama.com/function/edit_post_link)Displays edit post link (A html tag).*
-
- *[the\_date()](https://wp-kama.com/function/the_date "
")Displays/retrieves post publication date.*
- *[get\_the\_date()](https://wp-kama.com/function/get_the_date)Gets the post creation date.*
- *[the\_time()](https://wp-kama.com/function/the_time "
")Displays post publication date.*
- *[get\_post\_time()](https://wp-kama.com/function/get_post_time "get_post_time( $d, $gmt, $post, $translate );
")Gets time (date) of post publication.*
- *[the\_modified\_date()](https://wp-kama.com/function/the_modified_date "
")Displays time (date) when post was changed.*
-
- *[the\_post\_thumbnail()](https://wp-kama.com/function/the_post_thumbnail "
")Displays html code of post thumbnail image.*
- *[get\_post\_thumbnail\_id()](https://wp-kama.com/function/get_post_thumbnail_id)Gets the post thumbnail ID.*
- *[has\_post\_thumbnail()](https://wp-kama.com/function/has_post_thumbnail "
")Whether or not the post has a thumbnail. Conditional tag.*
- *[the\_post\_thumbnail\_url()](https://wp-kama.com/function/the_post_thumbnail_url "
")Displays the URL of the post thumbnail.*
- *[the\_attachment\_link()](https://wp-kama.com/function/the_attachment_link "
")Displays the link (A tag) of the attachment or the attachment page.*
- *[get\_attachment\_link()](https://wp-kama.com/function/get_attachment_link "$attachment_page = get_attachment_link( $id );
")Gets the URL to the attachment page.*
- *[wp\_get\_attachment\_link()](https://wp-kama.com/function/wp_get_attachment_link)Gets the link (A tag) of the attachment or the attachment page.*
-
- *[the\_tags()](https://wp-kama.com/function/the_tags)Displays links to the post tags.*
- *[the\_category()](https://wp-kama.com/function/the_category)Displays post categories as links.*
- *[the\_taxonomies()](https://wp-kama.com/function/the_taxonomies "
")Displays links <a> to the post terms.*
- *[in\_category()](https://wp-kama.com/function/in_category "if( in_category( $category, $post ) ){
// ...
}
")Checks if the post belongs to a category.*
- *[sticky\_class()](https://wp-kama.com/function/sticky_class "
")Displays a "sticky" class if it is a sticky post.*
- *[is\_sticky()](https://wp-kama.com/function/is_sticky "
")Checks if the post is sticky to the home page.*
- *[the\_meta()](https://wp-kama.com/function/the_meta "
")Displays post meta-fields in <li> list.*
- *[get\_post\_format()](https://wp-kama.com/function/get_post_format "$format = get_post_format( $post_id );
")Gets the post format: quote, status, video, audio.*
-
- *[the\_author()](https://wp-kama.com/function/the_author "
")Displays post's author name.*
- *[get\_the\_author()](https://wp-kama.com/function/get_the_author "$author = get_the_author();
")Gets post's author name (display\_name).*
- *[the\_author\_link()](https://wp-kama.com/function/the_author_link "
")Displays link (A tag) to the site of post's author.*
- *[get\_the\_author\_link()](https://wp-kama.com/function/get_the_author_link "get_the_author_link();
")Gets link (A tag) to the site of post's author.*
- *[the\_author\_posts()](https://wp-kama.com/function/the_author_posts "
")Displays the total number of posts written by the author.*
- *[the\_author\_posts\_link()](https://wp-kama.com/function/the_author_posts_link)Displays link (A tag) to the post author's archive page .*
- *[the\_author\_meta()](https://wp-kama.com/function/the_author_meta "
")Displays specified meta-field of the post author (wp user).*
- *[get\_the\_author\_meta()](https://wp-kama.com/function/get_the_author_meta "get_the_author_meta( $field, $user_id );
")Gets specified meta-field of the post author (wp user).*
- *[the\_modified\_author()](https://wp-kama.com/function/the_modified_author "
")Displays the name of the author who last modified the post.*
```
No posts.
```
```
No posts.
```
```
No posts.
```
```
5,
'offset' => 1,
'category' => 1
]);
if( $myposts ){
foreach( $myposts as $post ){
setup_postdata( $post );
?>
```
```
5,
'orderby' => 'comment_count',
] );
if ( $query->have_posts() ) {
while ( $query->have_posts() ) {
$query->the_post();
?>
```
## WP CLI
### [Core](https://wp-kama.com/handbook/wp-cli/wp/core):
```
# Download WordPress
wp core download --locale=ru_RU
# Generate wp-config.php:
wp core config --dbname=NAME --dbuser=USER --dbpass=PASS --dbprefix=wp_
# Create DB (based on wp-config.php)
wp db create
# Install WP to created DB
wp core install --url=example.com --title=Example --admin_user=supervisor \
--admin_email=info@example.com --admin_password=strongpassword
```
### [Post](https://wp-kama.com/handbook/wp-cli/wp/post):
```
# List posts:
wp post list
# Edit post:
wp post edit 1
# Post update:
wp post update 1 --post_title="Your New title..."
# Create posts:
wp post create --post_status=publish --post_title="Second Post" --edit
```
### [Post meta](https://wp-kama.com/handbook/wp-cli/wp/post#wp-post-meta-list):
```
# See all metas of post 18:
wp post meta list 18
# Get post meta value:
wp post meta get 18 meta_name
# Delete post meta by key:
wp post meta delete 18 meta_name
```
### [DB](https://wp-kama.com/handbook/wp-cli/wp/db):
```
# Create DB dump
wp db export - --add-drop-table --default-character-set=utf8mb4 | gzip > ./db-dump-$(date +%Y-%m-%d-%H%M%S).sql.gz
# Insert data from DB dump to DB
wp db import db_backup-2022-01-20.sql
# Login WordPress db:
wp db cli
# Run SQL Query:
wp db query "SELECT user_login, ID FROM wp_users;"
# Optimize db:
wp db optimize
```
### [Update](https://wp-kama.com/handbook/wp-cli/wp/core):
```
# Update WordPress
wp core update
# Update all plugins:
wp plugin update --all
```
### [Themes](https://wp-kama.com/handbook/wp-cli/wp/theme) & [Plugins](https://wp-kama.com/handbook/wp-cli/wp/plugin)
```
# List plugins:
wp plugin list
# Search plugin:
wp plugin search yoast
# Install plugin:
wp plugin install yoast
# List installed themes:
wp theme list
# Install theme:
wp theme install twentyone
# Activate theme:
wp theme activate twentyone
```
[Plugin Creation](https://developer.wordpress.org/plugins/)- *[register\_activation\_hook()](https://wp-kama.com/function/register_activation_hook)Registers the function **to activate the plugin**.*
- *[register\_deactivation\_hook()](https://wp-kama.com/function/register_deactivation_hook "register_deactivation_hook( $file, $function );
")Registers the function **to deactivate the plugin**.*
- *[register\_uninstall\_hook()](https://wp-kama.com/function/register_uninstall_hook "register_uninstall_hook( $file, $callback );
")Registers the function **for deleting the plugin**.*
-
- *[plugins\_url()](https://wp-kama.com/function/plugins_url "plugins_url( $path, $plugin );
")Gets **URL of plugins/mu plugins folder** (no slash at the end)\*\*.*
- *[plugin\_basename()](https://wp-kama.com/function/plugin_basename)**Path to plugin file** (from plugins folder).*
- *[plugin\_dir\_path()](https://wp-kama.com/function/plugin_dir_path "plugin_dir_path( $file );
")Gets **Path to plugin folder** (has slash at the end).*
- *[plugin\_dir\_url()](https://wp-kama.com/function/plugin_dir_url "$url = plugin_dir_url( $file );
")Gets **URL of the plugin folder** (has slash at the end).*
-
- *[get\_plugins()](https://wp-kama.com/function/get_plugins)Gets **data of plugins** (active and inactive).*
- *[get\_plugin\_data()](https://wp-kama.com/function/get_plugin_data "get_plugin_data( $plugin_file, $markup, $translate );
")Gets **data of the plugin from file headers**.*
-
- *[activate\_plugins()](https://wp-kama.com/function/activate_plugins "activate_plugins( $plugins, $redirect, $network_wide, $silent );
")Activates plugins.*
- *[deactivate\_plugins()](https://wp-kama.com/function/deactivate_plugins "deactivate_plugins( $plugins, $silent, $network_wide );
")Deactivates plugins.*
- *[is\_plugin\_active()](https://wp-kama.com/function/is_plugin_active)Checks if a plugin is **active**. Works only in the admin panel.*
[uninstall.php](https://wp-kama.com/handbook/plugins/osnovy/udalenie)
```
## Script and Style
[Script & Style functions](https://wp-kama.com/function-cat/scripts-and-styles)- *[wp\_register\_script()](https://wp-kama.com/function/wp_register_script "wp_register_script( $handle, $src, $deps, $ver, $in_footer );
")Registers the js file.*
- *[wp\_enqueue\_script()](https://wp-kama.com/function/wp_enqueue_script "wp_enqueue_script( $handle, $src, $deps, $ver, $in_footer );
")Registers and connects the js file.*
- *[wp\_dequeue\_script()](https://wp-kama.com/function/wp_dequeue_script "wp_dequeue_script( $handle );
")Deletes file from the output queue.*
- *[wp\_add\_inline\_script()](https://wp-kama.com/function/wp_add_inline_script)Adds JS code to the registered script.*
- *[wp\_deregister\_script()](https://wp-kama.com/function/wp_deregister_script)Unregisters the js file.*
- *[wp\_script\_add\_data()](https://wp-kama.com/function/wp_script_add_data "wp_script_add_data( $handle, $key, $value );
")Adds data to the script. Example: script only for "IE 6", "lt IE 9".*
- *[wp\_localize\_script()](https://wp-kama.com/function/wp_localize_script)Adds data before the specified script.*
- *[wp\_script\_is()](https://wp-kama.com/function/wp_script_is "wp_script_is( $handle, $list );
")Whether the file has been registered/waiting for output.*
-
- *[wp\_register\_style()](https://wp-kama.com/function/wp_register_style)Registers the css file.*
- *[wp\_enqueue\_style()](https://wp-kama.com/function/wp_enqueue_style "wp_enqueue_style( $handle, $src, $deps, $ver, $media );
")Registers and connects the css file.*
- *[wp\_dequeue\_style()](https://wp-kama.com/function/wp_dequeue_style "wp_dequeue_style( $handle );
")Deletes file from the output queue.*
- *[wp\_add\_inline\_style()](https://wp-kama.com/function/wp_add_inline_style "wp_add_inline_style( $handle, $data );
")Adds styles directly to the html document.*
- *[wp\_deregister\_style()](https://wp-kama.com/function/wp_deregister_style "wp_deregister_style( $handle );
")Unregisters the css file.*
- *[wp\_style\_add\_data()](https://wp-kama.com/function/wp_style_add_data "wp_style_add_data( $handle, $key, $value );
")Adds data to styles. Example: styles only for "IE 6", "lt IE 9".*
- *[wp\_style\_is()](https://wp-kama.com/function/wp_style_is "wp_style_is( $handle, $list );
")Whether the file has been registered/waiting for output.*
[How hooks work in WordPress](https://wp-kama.ru/handbook/codex/hooks)[Hooks execution order](https://wp-kama.com/hooks/actions-order)- *[add\_action()](https://wp-kama.com/function/add_action)Hangs a function on an event.*
- *[remove\_action()](https://wp-kama.com/function/remove_action "remove_action( $tag, $function_to_remove, $priority );
")Deletes a function from the event.*
- *[did\_action()](https://wp-kama.com/function/did_action)Gets a number of how many times the event was performed.*
- *[do\_action()](https://wp-kama.com/function/do_action)Creates an event.*
- *[do\_action\_ref\_array()](https://wp-kama.com/function/do_action_ref_array)Creates an event. Arguments are passed in an array.*
- *[has\_action()](https://wp-kama.com/function/has_action "$has = has_action( $tag, $function_to_check );
")Checks whether a function is hung on the event.*
- *[current\_action()](https://wp-kama.com/function/current_action)Gets the name of the current event.*
- *[doing\_action()](https://wp-kama.com/function/doing_action "doing_action( $action );
")Checks if the event is being processed at the moment.*
- *[remove\_all\_actions()](https://wp-kama.com/function/remove_all_actions "remove_all_actions( $tag, $priority );
")Deletes all functions attached to the event.*
-
- *[add\_filter()](https://wp-kama.com/function/add_filter)Hangs a function on a filter.*
- *[remove\_filter()](https://wp-kama.com/function/remove_filter)Deletes a function from the filter.*
- *[apply\_filters()](https://wp-kama.com/function/apply_filters)Creates a filter.*
- *[apply\_filters\_ref\_array()](https://wp-kama.com/function/apply_filters_ref_array "apply_filters_ref_array( $tag, $args );
")Creates a filter. Arguments are passed in an array.*
- *[has\_filter()](https://wp-kama.com/function/has_filter "has_filter( $tag, $function_to_check );
")Checks whether the function is hung on the filter.*
- *[current\_filter()](https://wp-kama.com/function/current_filter "$filter_name = current_filter();
")Gets the name of the current filter.*
- *[doing\_filter()](https://wp-kama.com/function/doing_filter "if( doing_filter( $filter_name ) ){
// ...
}
")Checks if the filter is currently being processed.*
- *[remove\_all\_filters()](https://wp-kama.com/function/remove_all_filters "remove_all_filters( $tag, $priority );
")Deletes all functions attached to the filter.*
```
function my_filter_function( $str ){
return 'Hello '. $str;
}
// Let's attach a function to the filter
add_filter( 'my_filter', 'my_filter_function' );
// Call the filter
echo apply_filters( 'my_filter', 'John' ); //> Hello John
```
```
// Create a function for the event
function my_action_function( $text ){
echo 'The my_action event has been triggered just now.';
}
// Let's attach the function to the my_action event
add_action( 'my_action', 'my_action_function' );
// Action call
do_action( 'my_action' ); //> The my_action event has been triggered just now.
```
## Localization (translation)
[Localization Functions](https://wp-kama.com/function-tag/localize)[Translations in WordPress](https://wp-kama.ru/handbook/codex/translations)- *[\_\_()](https://wp-kama.com/function/__ "$text = __( $text, $domain );
")Gets string translation.*
- *[\_e()](https://wp-kama.com/function/_e "
")Outputs a string translation.*
- *[\_n()](https://wp-kama.com/function/_n)Gets a string translation after a number.*
-
- *[esc\_attr\_\_()](https://wp-kama.com/function/esc_attr__)Gets string translation + esc\_attr().*
- *[esc\_attr\_e()](https://wp-kama.com/function/esc_attr_e)Outputs the string translation + esc\_attr().*
- *[esc\_html\_\_()](https://wp-kama.com/function/esc_html__)Gets the string translation + esc\_html().*
- *[esc\_html\_e()](https://wp-kama.com/function/esc_html_e)Outputs the string translation + esc\_html().*
-
- *[\_x()](https://wp-kama.com/function/_x)Gets the string translation for context.*
- *[\_ex()](https://wp-kama.com/function/_ex "
")Outputs the string translation for the context.*
- *[\_nx()](https://wp-kama.com/function/_nx)Gets a string translation after a number for the context.*
-
- *[date\_i18n()](https://wp-kama.com/function/date_i18n "date_i18n( $format, $timestamp_with_offset, $gmt );
")Gets the translated date. Localization for date().*
-
- *[determine\_locale()](https://wp-kama.com/function/determine_locale)Gets the locale of the site suitable for the current query.*
- *[get\_locale()](https://wp-kama.com/function/get_locale)Gets the locale of the site. E.g. en\_US.*
- *[get\_user\_locale()](https://wp-kama.com/function/get_user_locale)Gets the user's locale.*
- *[switch\_to\_locale()](https://wp-kama.com/function/switch_to_locale "switch_to_locale( $locale );
")Switches the user's locale.*
- *[is\_locale\_switched()](https://wp-kama.com/function/is_locale_switched "if( is_locale_switched() ){
// locale is switched
}
")Checks if switch\_to\_locale() was used.*
-
- *[load\_plugin\_textdomain()](https://wp-kama.com/function/load_plugin_textdomain)Loads .mo file **from plugin folder**.*
- *[load\_muplugin\_textdomain()](https://wp-kama.com/function/load_muplugin_textdomain "load_muplugin_textdomain( $domain, $mu_plugin_rel_path );
")Loads .mo file **from plugin's MU folder**.*
- *[load\_theme\_textdomain()](https://wp-kama.com/function/load_theme_textdomain "load_theme_textdomain( $domain, $path );
")Loads the .mo file **from the theme folder**.*
- *[load\_child\_theme\_textdomain()](https://wp-kama.com/function/load_child_theme_textdomain "load_child_theme_textdomain( $domain, $path );
")Loads the .mo file **from the child theme folder**.*
- *[load\_textdomain()](https://wp-kama.com/function/load_textdomain)Loads the specified .mo file **from any folder**.*
- *[is\_textdomain\_loaded()](https://wp-kama.com/function/is_textdomain_loaded "if( is_textdomain_loaded( $domain ) ){
// localization file is loaded - translation exists...
}
")Checks if the .mo file is loaded.*
- *[unload\_textdomain()](https://wp-kama.com/function/unload_textdomain "unload_textdomain( $domain );
")Unloads (removes) the loaded .mo file.*
## Conditional tags `(post types and queries)`
```
if( is_single() ){
// single post type page
}
```
- *[wp\_doing\_ajax()](https://wp-kama.com/function/wp_doing_ajax "if( wp_doing_ajax() ){
// this is AJAX request
}
")Works for an AJAX request in WordPress.*
- *[wp\_doing\_cron()](https://wp-kama.com/function/wp_doing_cron "if( wp_doing_cron() ){
// WP loaded through cron
}
")Works for WordPress cron requests.*
- *[is\_ssl()](https://wp-kama.com/function/is_ssl "if( is_ssl() ){
// ...
}
")Works for HTTPS (SSL).*
- *[is\_front\_page()](https://wp-kama.com/function/is_front_page "if( is_front_page() ) {
// code
}
")Home page.*
- *[is\_home()](https://wp-kama.com/function/is_home "if( is_home() ){
// code
}
")Posts page (or Home page).*
- *[is\_single()](https://wp-kama.com/function/is_single "if( is_single( $post ) ){
// ...
}
")Page of post of any type except: attachment and page.*
- *[is\_singular()](https://wp-kama.com/function/is_singular "if( is_singular($post_types) ){
// ...
}
")Page of post of any type.*
- *[is\_page()](https://wp-kama.com/function/is_page "if( is_page( $page ) ){
// code
}
")The page of a Static page.*
- *[is\_page\_template()](https://wp-kama.com/function/is_page_template "if( is_page_template( $template ) ){
// ...
}
")Whether or not a template file is used for the page.*
- *[is\_attachment()](https://wp-kama.com/function/is_attachment "if( is_attachment( $attachment ) ){
// attachment page
}
")Attachment page.*
- *[is\_search()](https://wp-kama.com/function/is_search "
")Search result page.*
- *[is\_archive()](https://wp-kama.com/function/is_archive "
")Archive page: category, tag, author, date.*
- *[is\_category()](https://wp-kama.com/function/is_category "if( is_category( $category ) ){
// code...
}
")Category page.*
- *[is\_tag()](https://wp-kama.com/function/is_tag "if( is_tag() ){
// code
}
")Tag page.*
- *[is\_tax()](https://wp-kama.com/function/is_tax "if( is_tax( $taxonomy, $term ) ){
// it is taxonomy...
}
")Page of custom taxonomy.*
- *[is\_post\_type\_archive()](https://wp-kama.com/function/is_post_type_archive "if( is_post_type_archive( $post_types ) ){
// ...
}
")Page of custom post type archive.*
- *[is\_author()](https://wp-kama.com/function/is_author "if( is_author() ){
// ...
}
")Page of author posts archive.*
- *[is\_date()](https://wp-kama.com/function/is_date)Archive page by date.*
- *[is\_year()](https://wp-kama.com/function/is_year "if( is_year() ){
// ...
}
")Archive page by Year.*
- *[is\_month()](https://wp-kama.com/function/is_month "if( is_month() ){
// ...
}
")Archive page by Month.*
- *[is\_day()](https://wp-kama.com/function/is_day "if( is_day() ){
// ...
}
")Archive page by Day.*
- *[is\_time()](https://wp-kama.com/function/is_time)Archive page by an hour, minute, second.*
- *[is\_paged()](https://wp-kama.com/function/is_paged "if( is_paged() ){
// ...
}
")Pagination page.*
- *[is\_404()](https://wp-kama.com/function/is_404)"Not found" page.*
- *[is\_preview()](https://wp-kama.com/function/is_preview)Post preview page.*
- *[is\_feed()](https://wp-kama.com/function/is_feed "if( is_feed( $feeds ) ){
...
}
")Feed page.*
- *[is\_admin()](https://wp-kama.com/function/is_admin "if( is_admin() ){
// ...
}
")Admin panel.*
- *[is\_network\_admin()](https://wp-kama.com/function/is_network_admin "if( is_network_admin() ){
// we are in network administration
}
")Administration panel "Network management" of Multisite sites.*
- *[is\_blog\_admin()](https://wp-kama.com/function/is_blog_admin)Section of the admin panel of a separate site in Multisite.*
- *[is\_user\_admin()](https://wp-kama.com/function/is_user_admin "if( is_user_admin() ){
//
}
")The "User" section of the admin panel in Multisite.*
- *[is\_customize\_preview()](https://wp-kama.com/function/is_customize_preview)Page of customizer in the admin area.*
- *[is\_robots()](https://wp-kama.com/function/is_robots "if( is_robots() ){
// this is robots.txt file
}
")Query to the robots.txt file.*
- *[is\_embed()](https://wp-kama.com/function/is_embed "if( is_embed() ){
// request for the embed post page
}
")Page of embedding post.*
- *[is\_comment\_feed()](https://wp-kama.com/function/is_comment_feed "if( is_comment_feed() ){
// comment feed page.
}
")Comments feed page.*
- *[is\_trackback()](https://wp-kama.com/function/is_trackback "if( is_trackback() ){
// ping request
}
")Page of pings (trackback).*
```
if( is_user_logged_in() ){
// user is authorized
}
```
- *[is\_user\_logged\_in()](https://wp-kama.com/function/is_user_logged_in "if ( is_user_logged_in() ) {
// ...
}
")Checks if the user is logged in.*
- *[have\_comments()](https://wp-kama.com/function/have_comments "if( have_comments() ){
// there are comments, we display them
}
")Checks if there are comments to be displayed on the page.*
- *[comments\_open()](https://wp-kama.com/function/comments_open "comments_open( $post_id );
")Checks if comments are opened.*
- *[has\_category()](https://wp-kama.com/function/has_category)Checks if the post is in at least one category.*
- *[has\_tag()](https://wp-kama.com/function/has_tag "has_tag( $tag, $post );
")Checks if the post is in at least one tag.*
- *[has\_term()](https://wp-kama.com/function/has_term "if( has_term( $term, $taxonomy, $post ) ){
...
}
")Checks if the post is in at least one taxonomy term.*
- *[has\_excerpt()](https://wp-kama.com/function/has_excerpt "if( has_excerpt( $id ) ){
// ...
}
")Checks if the post has an excerpt (quote, short description).*
- *[is\_nav\_menu()](https://wp-kama.com/function/is_nav_menu "is_nav_menu( $menu );
")Checks if there is a menu by ID, slug or name.*
- *[has\_nav\_menu()](https://wp-kama.com/function/has_nav_menu "if( has_nav_menu( $location ) ){
// ...
}
")Checks if registered menu area have an attached menu.*
- *[has\_shortcode()](https://wp-kama.com/function/has_shortcode "if ( has_shortcode( $content, $tag ) ) { }
")Checks if content contains the specified shortcode.*
- *[shortcode\_exists()](https://wp-kama.com/function/shortcode_exists "if ( shortcode_exists( $tag ) ) { }
")Checks if the specified shortcode is registered.*
- *[in\_category()](https://wp-kama.com/function/in_category "if( in_category( $category, $post ) ){
// ...
}
")Checks if the post are in a category.*
- *[in\_the\_loop()](https://wp-kama.com/function/in_the_loop "if( in_the_loop() ){
// we inside the loop...
}
")Checks if we are inside a WP Loop.*
- *[is\_main\_query()](https://wp-kama.com/function/is_main_query "if( is_main_query() ){ ... };
")Checks if we are in the main WP Loop.*
- *[is\_active\_sidebar()](https://wp-kama.com/function/is_active_sidebar "if( is_active_sidebar( $index ) ){
// code
}
")Checks if there is at least one widget in the widgets area.*
- *[is\_child\_theme()](https://wp-kama.com/function/is_child_theme "if( is_child_theme() ){
// child theme
}
")Checks if a child theme being used.*
- *[is\_dynamic\_sidebar()](https://wp-kama.com/function/is_dynamic_sidebar "is_dynamic_sidebar();
")Checks if theme sidebars are enabled and they has at least one widget.*
- *[is\_local\_attachment()](https://wp-kama.com/function/is_local_attachment "if( is_local_attachment( $url ) ){
// this is a file from the WordPress media library
}
")Checks if the given URL is an attachment page.*
- *[is\_multisite()](https://wp-kama.com/function/is_multisite "if ( is_multisite() ) {
echo 'Мультисайтовость включена';
}
")Checks if the multisite mode is turned on.*
- *[is\_new\_day()](https://wp-kama.com/function/is_new_day "
")Checks if the current date differs from the previous (in the loop).*
- *[is\_post\_type\_hierarchical()](https://wp-kama.com/function/is_post_type_hierarchical)Checks if the post type is hierarchical (tree-like).*
- *[is\_taxonomy\_hierarchical()](https://wp-kama.com/function/is_taxonomy_hierarchical "if( is_taxonomy_hierarchical( $taxonomy ) ){
// do something
}
")Checks if the taxonomy is hierarchical (tree-like).*
- *[is\_sticky()](https://wp-kama.com/function/is_sticky "
")Checks if the post is sticky (be shown on front page).*
- *[pings\_open()](https://wp-kama.com/function/pings_open "
")Checks if the post is allowed to receive pings.*
- *[post\_exists()](https://wp-kama.com/function/post_exists "post_exists( $title, $content, $date );
")Checks if there is a post with a specified title (post\_title).*
- *[taxonomy\_exists()](https://wp-kama.com/function/taxonomy_exists "
")Checks if the specified taxonomy exist.*
- *[post\_password\_required()](https://wp-kama.com/function/post_password_required "if( post_password_required( $post ) ){ ... }
")Checks if the post is password protected and it is correct.*
- *[term\_exists()](https://wp-kama.com/function/term_exists)Checks if the taxonomy element exist (return the term ID).*
- *[cat\_is\_ancestor\_of()](https://wp-kama.com/function/cat_is_ancestor_of)Checks if the category is child of another one (all nesting levels).*
- *[term\_is\_ancestor\_of()](https://wp-kama.com/function/term_is_ancestor_of "if( term_is_ancestor_of( $term1, $term2, $taxonomy ) ){
// there is a dependency
}
")Checks if the term is child of another one (all nesting levels).*
- *[wp\_attachment\_is()](https://wp-kama.com/function/wp_attachment_is "wp_attachment_is( $type, $post_id );
")Checks if the attachment is an image, audio or video.*
- *[wp\_attachment\_is\_image()](https://wp-kama.com/function/wp_attachment_is_image "wp_attachment_is_image( $post );
")Checks if the attachment (post) is a image .*
- *[is\_header\_video\_active()](https://wp-kama.com/function/is_header_video_active "if( has_header_video() && is_header_video_active() ){
// ...
}
")Checks if the header video should be shown on the page.*
- *[has\_custom\_header()](https://wp-kama.com/function/has_custom_header "if( has_custom_header() ){
// video or image is set for the theme header
}
")Checks if the picture/video is set for the theme header.*
- *[wp\_is\_mobile()](https://wp-kama.com/function/wp_is_mobile "if( wp_is_mobile() ){ ... }
")Checks if the site is viewed on a mobile device.*
- *[wp\_is\_post\_autosave()](https://wp-kama.com/function/wp_is_post_autosave "wp_is_post_autosave( $post );
")Checks if the post is an auto-save.*
- *[wp\_is\_post\_revision()](https://wp-kama.com/function/wp_is_post_revision "wp_is_post_revision( $post );
")Checks if the post is a revision.*
## Template Tags
[All Template Tags](https://wp-kama.com/functions/template-tags)- *[home\_url()](https://wp-kama.com/function/home_url)Gets the URL of the homepage.*
- *[site\_url()](https://wp-kama.com/function/site_url "site_url( $path, $scheme );
")Gets the URL of the admin panel.*
- *[wp\_get\_document\_title()](https://wp-kama.com/function/wp_get_document_title "<?php echo wp_get_document_title(); ?>
")Gets the page title for <title>.*
- *[the\_archive\_title()](https://wp-kama.com/function/the_archive_title)Outputs the title of the archive page: tag, category, date.*
- *[single\_term\_title()](https://wp-kama.com/function/single_term_title "
")Outputs/Gets the title of the term page.*
- *[single\_post\_title()](https://wp-kama.com/function/single_post_title)Outputs/Gets title of a post page.*
- *[single\_cat\_title()](https://wp-kama.com/function/single_cat_title "
")Outputs/Gets title of a category/tag page.*
- *[body\_class()](https://wp-kama.com/function/body_class)Outputs css classes for the <body> tag.*
- *[wp\_body\_open()](https://wp-kama.com/function/wp_body_open "> ...
")Triggers the [wp\_body\_open](https://wp-kama.com/hook/wp_body_open) hook. Use is after <body> tag.*
- *[wp\_head()](https://wp-kama.com/function/wp_head "
")Triggers the [wp\_head](https://wp-kama.com/hook/wp_head) hook. Use it in header.php file.*
- *[wp\_footer()](https://wp-kama.com/function/wp_footer "
")Triggers the [wp\_footer](https://wp-kama.com/hook/wp_footer) hook. Use it in footer.php file.*
- *[wp\_list\_categories()](https://wp-kama.com/function/wp_list_categories "
")Outputs list of categories as links.*
- *[wp\_dropdown\_categories()](https://wp-kama.com/function/wp_dropdown_categories)Outputs a dropdown list of categories/terms.*
- *[wp\_list\_comments()](https://wp-kama.com/function/wp_list_comments "
")Outputs/Gets post comments.*
- *[comment\_form()](https://wp-kama.com/function/comment_form "comment_form( $args, $post_id );
")Outputs comment form.*
- *[wp\_tag\_cloud()](https://wp-kama.com/function/wp_tag_cloud "
")Outputs/Gets tag cloud.*
- *[register\_sidebar()](https://wp-kama.com/function/register_sidebar "register_sidebar( $args );
")Registers a widget panel.*
- *[register\_sidebars()](https://wp-kama.com/function/register_sidebars)Registers a widget panels (several at once).*
- *[wp\_nav\_menu()](https://wp-kama.com/function/wp_nav_menu "
")Outputs a custom menu created in the admin panel.*
- *[register\_nav\_menu()](https://wp-kama.com/function/register_nav_menu "
")Registers a single menu location (area).*
- *[register\_nav\_menus()](https://wp-kama.com/function/register_nav_menus)Registers multiple menu locations (areas).*
- *[wp\_get\_attachment\_image()](https://wp-kama.com/function/wp_get_attachment_image "$img = wp_get_attachment_image( $attachment_id, $size, $icon, $attr );
")Gets image IMG tag.*
- *[wp\_get\_attachment\_image\_src()](https://wp-kama.com/function/wp_get_attachment_image_src)Gets image data: URL/Width/Height.*
- *[wp\_get\_attachment\_image\_url()](https://wp-kama.com/function/wp_get_attachment_image_url "wp_get_attachment_image_url( $attachment_id, $size, $icon );
")Gets image URL by it's ID.*
- *[category\_description()](https://wp-kama.com/function/category_description "$description = category_description( $category_id );
")Gets category description.*
- *[term\_description()](https://wp-kama.com/function/term_description "term_description( $term, $deprecated );
")Gets term description.*
- *[get\_the\_term\_list()](https://wp-kama.com/function/get_the_term_list)Outputs a list of post terms as links.*
- *[get\_avatar()](https://wp-kama.com/function/get_avatar "get_avatar( $id_or_email, $size, $default, $alt, $args );
")Gets image of the user avatar (<img> tag).*
- *[next\_post\_link()](https://wp-kama.com/function/next_post_link "next_post_link( $format, $link, $in_same_term, $excluded_terms, $taxonomy );
")Displays a link to the next most recent post (by date).*
- *[previous\_post\_link()](https://wp-kama.com/function/previous_post_link "
")Displays a link to the previous most recent post (by date).*
- *[get\_post\_type\_archive\_link()](https://wp-kama.com/function/get_post_type_archive_link)Gets the URL for the post type archive page.*
- *[wp\_link\_pages()](https://wp-kama.com/function/wp_link_pages "
")Outputs pagination for multi-page post <!--nextpage-->.*
- *[the\_post\_navigation()](https://wp-kama.com/function/the_post_navigation "
")Outputs links to next/previous posts (as HTML block).*
- *[wp\_get\_archives()](https://wp-kama.com/function/wp_get_archives "wp_get_archives( $args );
")Outputs links to date archives pages: days, months, years.*
- *[wp\_login\_form()](https://wp-kama.com/function/wp_login_form "
")Outputs login form HTML code.*
- *[edit\_tag\_link()](https://wp-kama.com/function/edit_tag_link "
")Outputs a link to edit the current tag.*
- *[edit\_term\_link()](https://wp-kama.com/function/edit_term_link)Outputs a link to edit the current term.*
## Formatting
[Formatting](https://wp-kama.com/function-cat/formatting)- *[absint()](https://wp-kama.com/function/absint)Convert a value to non-negative integer.*
- *[antispambot()](https://wp-kama.com/function/antispambot)Converts all email characters to HTML entities.*
- *[force\_balance\_tags()](https://wp-kama.com/function/force_balance_tags "force_balance_tags( $text );
")Fixes HTML tags: not closed, wrong syntax.*
- *[links\_add\_target()](https://wp-kama.com/function/links_add_target "links_add_target( $content, $target, $tags );
")Adds a target attr with the specified value to A tags.*
- *[make\_clickable()](https://wp-kama.com/function/make_clickable "$text = make_clickable( $text );
")Changes links like http://site.com, www.site.com to HTML link.*
- *[normalize\_whitespace()](https://wp-kama.com/function/normalize_whitespace "normalize_whitespace( $str );
")Replaces all line breaks (EOL) with \\n, removes extra spaces.*
- *[number\_format\_i18n()](https://wp-kama.com/function/number_format_i18n "number_format_i18n( $number, $decimals = 0 );
")Corrects integer or decimal number format to fit localisation.*
- *[size\_format()](https://wp-kama.com/function/size_format)Changes bytes to format: 500 B, 63 KB, 9 MB, 2 GB, 1 TB.*
- *[set\_url\_scheme()](https://wp-kama.com/function/set_url_scheme)Fixs URL protocol. If set "relative" domain will be removed.*
- *[wp\_rel\_nofollow()](https://wp-kama.com/function/wp_rel_nofollow)Adds rel="nofollow" to all <a>. Internal links are skipped.*
- *[trailingslashit()](https://wp-kama.com/function/trailingslashit "$string = trailingslashit( $string );
")Adds a slash (/) to the end of string (URL/path).*
- *[untrailingslashit()](https://wp-kama.com/function/untrailingslashit "$url = untrailingslashit( $url );
")Removes closing slash (/) at the end of a string.*
- *[user\_trailingslashit()](https://wp-kama.com/function/user_trailingslashit "user_trailingslashit( $string, $type_of_url );
")Adds or removes a slash (/) at the end. Depends on WP permalink settings.*
- *[wp\_trim\_words()](https://wp-kama.com/function/wp_trim_words)Trims text to the specified number of words.*
- *[wpautop()](https://wp-kama.com/function/wpautop "$pee = wpautop( $text, $br );
")Replaces double newline (\\n\\n) with HTML <p>...</p> and single with <br>.*
- *[wptexturize()](https://wp-kama.com/function/wptexturize "wptexturize( $text, $reset );
")Changes some characters in the text: (tm) >> ™ etc.*
- *[zeroise()](https://wp-kama.com/function/zeroise)Add leading zeros when necessary: 10 >> 0010.*
## Escaping on output
[Escaping on output](https://wp-kama.com/function-tag/esc_)- *[esc\_attr()](https://wp-kama.com/function/esc_attr "
")Cleans for use in HTML tag attribute.*
- *[esc\_html()](https://wp-kama.com/function/esc_html "esc_html( $text );
")Cleans for displaying text on the screen.*
- *[esc\_url()](https://wp-kama.com/function/esc_url "$url = esc_url( $url, $protocols, $_context );
")Cleans for use in the src=, url=, etc. attributes.*
- *[esc\_textarea()](https://wp-kama.com/function/esc_textarea)Cleans for use in <textarea> value.*
- *[wp\_strip\_all\_tags()](https://wp-kama.com/function/wp_strip_all_tags)Removes all HTML tags.*
- *[wp\_kses()](https://wp-kama.com/function/wp_kses "wp_kses( $string, $allowed_html, $allowed_protocols );
")Removes all HTML tags.*
- *[esc\_js()](https://wp-kama.com/function/esc_js)Prepares string for display in JS.*
- *[esc\_sql()](https://wp-kama.com/function/esc_sql)Cleans the string, leaving only the specified HTML tags.*
## Sanitize on input
[Sanitize on input](https://wp-kama.com/function-tag/check-sanitize)- *[sanitize\_text\_field()](https://wp-kama.com/function/sanitize_text_field)Cleans string, leaving only clean text: without HTML, extra spaces, etc.*
- *[sanitize\_textarea\_field()](https://wp-kama.com/function/sanitize_textarea_field)Cleans string for textarea (when saving to the database).*
- *[sanitize\_key()](https://wp-kama.com/function/sanitize_key)Cleans string to use it as a key/ID.*
- *[sanitize\_url()](https://wp-kama.com/function/sanitize_url "sanitize_url( $url, $protocols );
")Cleans string to use it for redirects or to store it in the DB.*
- *[sanitize\_html\_class()](https://wp-kama.com/function/sanitize_html_class "$sanitized = sanitize_html_class( $class, $fallback );
")Cleans the text for use in the HTML attribute "class".*
- *[sanitize\_email()](https://wp-kama.com/function/sanitize_email "$email = sanitize_email( $email );
")Cleans string, leaving only the permissible characters for an email.*
- *[sanitize\_file\_name()](https://wp-kama.com/function/sanitize_file_name "sanitize_file_name( $filename );
")Cleans the file name, replacing " " with "\_" and removing impermissible characters.*
- *[sanitize\_title\_with\_dashes()](https://wp-kama.com/function/sanitize_title_with_dashes "
")Cleans title, replacing " " with "-".*
- *[sanitize\_mime\_type()](https://wp-kama.com/function/sanitize_mime_type "sanitize_mime_type( $mime_type );
")Removes all characters except "-+\*\*.a-zA-Z0-9/." - allowed in MIME type.*