I'd like to create a custom search (not just a custom form) as described in the second part of this article on wpmudev:
Sadly, this post doesn't have code I can model to create my own!
Let's say I have a custom post type Book, with a custom field Author, and custom taxonomy Genre.
I'd like a custom search form, limited to the Book CPT, where a visitor can choose to search for:
a term in the title or content of the Book (text search box), the author (text search box), and the genre (drop down select box).
If any of these is left blank, the search would ignore that aspect of the search. So if a person wanted to search for a Book with the word "ghost" in it of the genre "suspense," the author aspect of the search would be ignored, since the person didn't fill that field in.
Could you please tell me how to set up a WP Query object to perform this search, as well as a new search form and a search results page?