Advanced search form with filters for custom taxonomies and custom fields

I’d like to build an advanced search form for a specific custom post type, having filters for the custom post types custom fields, custom taxonomies, and for a separate custom post types properties (fields and taxonomies) which will be links to the first post type using a custom relationship field.

I’ve recently started off with WPs custom post types, fields, and taxonomies, I love it so far but to make the best of it I’d like to be able to search it properly. Do I need to do it manually? If so, how?

PS. If it matters, I’m using the plugins: Advanced Custom Fields and Custom Post Type UI.

Below I’ve mocked up an example of how the filtering would look and how it might relate to the post types above.

I think something like this you would be best writing yourself.

Take a look at: http://www.catalysthomes.co.uk/homes-for-sale/

Properties are loaded into a CPT and I have my own custom search in the sidebar. Of that search its searching a number of things such as taxonomies, custom fields and ordering by date price etc.

So how do I achieve this? I submit the form to a page template and from there I deal with the post data and build a new WP_query based on the search criteria. I use sessions to store the search variables so that I can paginate the results.

WP_Query is very powerful. Take a look: http://codex.wordpress.org/Class_Reference/WP_Query

In there you can use meta_query to query multiple custom fields and use tax_query to query your taxonomies, plus there is more. Below is how mine is built to give you an idea.

Template File:

  <?php
  $temp = $wp_query;
  $wp_query = NULL;
  $args = array();
  ?>

  <?php include("functions/Homes-for-sale/propertyrawresults.php"); ?>
  <?php include("functions/Homes-for-sale/propertysearchresults.php"); ?>

  <?php
  $args['post_type'] = "homes-for-sale";
  $args['showposts'] = 10;
  $args['paged'] = $paged;
  $wp_query = new WP_Query($args);
  ?>

  <?php include("functions/Homes-for-sale/propertylistlayout.php"); ?>

Raw Results

<?php
if($_POST['sortby']) {
    $_SESSION['prop_selectedsortby'] = $_POST['sortby'];
}

switch($_SESSION['prop_selectedsortby']) {
    case "name-asc": $args['order'] = "ASC"; $args['orderby'] = "title"; break;
    case "name-desc": $args['orderby'] = "title"; break;
    case "price-asc": $args['order'] = "ASC"; $args['orderby'] = "meta_value_num"; $args['meta_key'] = "chb_homes_for_sale_specifics_fmv"; break;
    case "price-desc": $args['orderby'] = "meta_value_num"; $args['meta_key'] = "chb_homes_for_sale_specifics_fmv"; break;
    case "date-asc": $args['order'] = "ASC"; break;
    default: /* No need to set arguments here as wp query defaults */ break;
}

$selectedsortby[$_SESSION['prop_selectedsortby']] = " selected=\"selected\"";
?>

Search Results

<?php
if( ! empty( $_SESSION['s_property_ptype'] ) ) {
    $args['meta_query'][] = array(
        'key' => 'chb_homes_for_sale_types_nbrs',
        'value' => $_SESSION['s_property_ptype']
    );
}

if( ! empty( $_SESSION['s_property_development'] ) ) {
    $args['meta_query'][] = array(
        'key' => 'chb_homes_for_sale_ofdevelopment',
        'value' => $_SESSION['s_property_development']
    );
}

if( isset( $_SESSION['s_property_area'] ) && 0 != $_SESSION['s_property_area'] ) {
    $args['tax_query'][] = array(
        'taxonomy' => 'areas',
        'field' => 'id',
        'terms' => array( (int) $_SESSION['s_property_area'] ),
    );
}

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_bedrooms',
    'value' => $_SESSION['s_property_bedrooms_min'],
    'compare' => '>=',
    'type' => 'SIGNED'
);

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_bedrooms',
    'value' => $_SESSION['s_property_bedrooms_max'],
    'compare' => '<=',
    'type' => 'SIGNED'
);

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_bathrooms',
    'value' => $_SESSION['s_property_bathrooms_min'],
    'compare' => '>=',
    'type' => 'SIGNED'
);

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_bathrooms',
    'value' => $_SESSION['s_property_bathrooms_max'],
    'compare' => '<=',
    'type' => 'SIGNED'
);

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_fmv',
    'value' => $_SESSION['s_property_min_price'],
    'compare' => '>=',
    'type' => 'SIGNED'
);

$args['meta_query'][] = array(
    'key' => 'chb_homes_for_sale_specifics_fmv',
    'value' => $_SESSION['s_property_max_price'],
    'compare' => '<=',
    'type' => 'SIGNED'
);
?>

List Layout
Just a standard WP loop to show post excerpts and info.