add_query_arg()

add_query_arg() — Retrieves a modified URL query string. You can rebuild the URL and append query variables to the URL query by using this function. There are two ways to use this function; either a single key and value, or an associative array. Using a single key and value: add_query_arg( ‘key’, ‘value’, ‘http://example.com’ ); Using an associative array: add_query_arg( array( ‘key1’ => ‘value1’, ‘key2’ => ‘value2’, ), ‘http://example.com’ ); Omitting the URL from either use results in the current URL being used (the value of $_SERVER[‘REQUEST_URI’]). Values are expected to be encoded appropriately with urlencode() or rawurlencode().

Inputs: $key (string|array): Either a query variable key, or an associative array of query variables. $value (string): Optional. Either a query variable value, or a URL to act upon. $url (string): Optional. A URL to act upon.

Returns string: New URL query string (unescaped).