Using WordPress ‘kses_init()’ PHP function
Sets up most of the KSES filters for input form content.
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Using WordPress ‘js_escape()’ PHP function
Escape single quotes, specialchar double quotes, and fix line endings.
Using WordPress ‘is_year()’ PHP function
Determines whether the query is for an existing year archive.
Using WordPress ‘is_wp_version_compatible()’ PHP function
Learn how to check WordPress compatibility using the `is_wp_version_compatible()` function in this article
Using WordPress ‘is_wp_error()’ PHP function
Checks whether the given variable is a WordPress Error.
Using WordPress ‘is_wpmu_sitewide_plugin()’ PHP function
Deprecated functionality for determining if the current plugin is network-only.
Using WordPress ‘is_user_spammy()’ PHP function
Determines whether a user is marked as a spammer, based on user login.
Using WordPress ‘is_user_option_local()’ PHP function
Check whether a usermeta key has to do with the current blog.
Using WordPress ‘is_user_member_of_blog()’ PHP function
Finds out whether a user is a member of a given blog.