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function is not described

_wp_sanitize_utf8_in_redirect() WP 4.2.0

URL encode UTF-8 characters in a URL.

  • See: wp_sanitize_redirect()

This is a pluggable function, and it can be replaced from plugin. It means that this function is defined (works) only after all plugins are connected (included), but before this moment the function has not yet been defined... Therefore, you cannot call this and all functions depended on this function directly from a plugin code. It must be called via hook plugins_loaded or later, for example on hook init.

Function replacement (override) — in a plugin you can create a function with the same name, then it will replace this function.

No Hooks.

Return

String. URL-encoded version of the first RegEx match.

Usage

_wp_sanitize_utf8_in_redirect( $matches );
$matches(array) (required)
RegEx matches against the redirect location.

Code of wp sanitize utf8 in redirect: wp-includes/pluggable.php VER 5.0.3

<?php
function _wp_sanitize_utf8_in_redirect( $matches ) {
	return urlencode( $matches[0] );
}