Ensures a string is a valid SQL ‘order by’ clause.

Sanitizes a string from user input or from the database.

Sanitizes a multiline string from user input or from the database.

Sanitizes a string into a slug, which can be used in URLs or HTML attributes.

Sanitizes a title with the ‘query’ context.

Sanitizes a title, replacing whitespace and a few other characters with dashes.

Sanitizes space or carriage return separated URLs that are used to send trackbacks.

Performs esc_url() for database or redirect usage.

Sanitizes a username, stripping out unsafe characters.

Checks to see if a string is utf8 encoded.