Checks (category)
| is_admin_bar_showing() | Determine whether the admin bar should be showing. |
| is_blog_installed() | Test whether WordPress is already installed. |
| is_countable() | Polyfill for is_countable() function added in PHP 7.3. |
| is_email() | Verifies that an email is valid. |
| is_iterable() | Polyfill for is_iterable() function added in PHP 7.1. |
| is_php_version_compatible() | Checks compatibility with the current PHP version. |
| is_serialized() | Check the given value if it's a serialized string. |
| is_serialized_string() | Check whether serialized data is of string type. |
| is_wp_error() | Checks whether the passed variable is a WordPress Error. |
| is_wp_version_compatible() | Checks compatibility with the current WordPress version. |
| seems_utf8() | Checks to see if a string is UTF-8 encoded. |
| wp_doing_ajax() | Determines whether the current request is a WordPress Ajax request. |
| wp_is_https_supported() | Checks whether HTTPS is supported for the server and domain. |
| wp_is_json_request() | Checks whether current request is a JSON request, or is expecting a JSON response. |
| wp_is_numeric_array() | Checks if the specified variable is an numeric-indexed array. |
| wp_is_using_https() | Checks whether the website is using HTTPS. |
| wp_validate_boolean() | Turns the value of the specified variable into a logical true or false. |