Common WordPress Conditional Functions

Posted in Articles

Here are some common WordPress conditional functions. Note that this is not an inclusive list.

Conditional Tag:

• is_home() – blog home
• is_front_page() – site front page
• is_single() – single post
• is_page()
• is_attachment() – if on an attachment page (such as an image)
• is_singular() – returns true for any is_single, is_page, or is_attachment
• is_category() – when a category page is being displayed
• is_tag() – when a tag page is being displayed
• is_archive() – returns true if on archive page
• is_search() – returns true if on search page
• is_author() – when author page is being displayed

Other:

• is_404() – when page not found is being displayed
• is_paged() – if archive or main page is split into several page, this returns true on second and subsequent pages.
• is_preview() – if displayed in preview mode.
• is_sticky() – if the post is sticky
• has_tag() – pass in tag or array of tags, returns true if post has this tag
• has_excerpt() – if the post has an excerpt
• has_post_thumbnail() – returns true if post has Featured image
• is_page_template() – pass in a template file with extension, returns true if this template is being used

Archives

• is_date() – when a date-based archive page is being displayed
• is_year()
• is_month()
• is_day()
• is_time()
• is_new_day()

Taxonomy:

• is_tax() – when any taxonomy archive page is being displayed
• has_term() – check if post has certain terms for taxonomy
• taxonomy_exists()
• is_taxonomy_hierarchical()

Admin:

• is_admin()
• is_user_logged_in()
• is_super_admin() – returns true if user is super admin in a Multi-site.  If not in Multi-site, returns true if user is an admin
• is_admin_bar_showing()

 

Post type:

• is_post_type_archive() – pass in a post_type, returns true if archive of that post type
• is_post_type_hierarchical() – pass in a post_type, returns true if this post_type was registered as having support for hierarchical

Comments and Pings

• is_comments_popup() – true when in comments popup window
• comments_open()
• pings_open()
• is_trackback()
• is_feed()

Misc:

• has_nav_menu() – pass in menu location slug, returns true if this location has menu
• in_the_loop() – when inside the loop
• is_main_query()
• is_active_sidebar() – pass in the sidebar name, id, or number, returns true if this sidebar is being used.
• is_dynamic_sidebar() – True if the current sidebar has active widgets
• is_active_widget()
• is_blog_installed()
• is_rtl()
• is_multisite() – if current site is in a Multi-site install
• is_main_site() – if current site is the main site in a multi-site install
• is_child_theme()
• current_theme_supports()
• is_multi_author() – returns true if more than one author on this site. Returns false if one or no authors.
• wp_attachment_is_image() – returns true if the attachment extension is .jpg, .jpeg, .gif, or .png.
• wp_script_is() – Determine if a script has been registered, enqueued, printed, or is waiting to be printed.

If exists:

• email_exists() –  check whether or not a given email address ($email) has already been registered to a username, and returns that users ID
• username_exists() – Returns the user ID if the user exists or null if the user doesn’t exist.
• post_type_exists()
• taxonomy_exists()
• term_exists()

Plugin:

• is_plugin_active()
• is_plugin_active_for_network()
• is_plugin_inactive()
• is_plugin_page()

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