Calls to_param on all its elements and joins the result with slashes. This is used by url_for in Action Pack.
Converts an array into a string suitable for use as a URL query string, using the given key as the param name.
['Rails', 'coding'].to_query('hobbies') # => "hobbies%5B%5D=Rails&hobbies%5B%5D=coding"
[Validate]