get the custom post type data using a custom field

问题:

Can I get the data using custom field value? My post_type is brand-name and the field name is generic-name. So How can I get all the data using the generic-name?

Here is the code:

$title = get_the_title(); 
$the_query = new WP_Query( array(
          'posts_per_page'=>9,
          'post_type'=>'brand-name',
          'order'   => 'ASC',
          'meta_query' => array(
           array(
                'key' => 'generic-name',// this key is advance custom field: type post_object
                'value' => $title,
                'type'  => 'char' // type not working
           ), 
        ), 
        'paged' => get_query_var('paged') ? get_query_var('paged') : 1) 
      );`

This code was not working.

回答1:

Your AFC field is a post object, which means the meta value is either a single post id, or a serialized array of post ids.

If your custom field is set to only allow a single selection, then it will be a single id, and can be queried like this:

$post_id = get_the_ID(); 
$the_query = new WP_Query( array(
      'posts_per_page'=>9,
      'post_type'=>'brand-name',
      'order'   => 'ASC',
      'meta_query' => array(
       array(
            'key' => 'generic-name',// this key is advance custom field: type post_object
            'value' => $post_id,
       ), 
    ), 
    'paged' => get_query_var('paged') ? get_query_var('paged') : 1) 
  );`

If your custom field allows multiple selection, then it will a serialized php array of ids. Since mysql does not know how to read php serialized data, the best you can do is use a LIKE query:

$post_id = get_the_ID(); 
$the_query = new WP_Query( array(
      'posts_per_page'=>9,
      'post_type'=>'brand-name',
      'order'   => 'ASC',
      'meta_query' => array(
       array(
            'key' => 'generic-name',// this key is advance custom field: type post_object
            'value' => sprintf("\"%s\"", $post_id),
            'compare' => 'LIKE'
       ), 
    ), 
    'paged' => get_query_var('paged') ? get_query_var('paged') : 1) 
  );`

回答2:

I think this may help you. Please have a look at this.

Can I get the data using custom field value? -- Yes, you can get the data using custom field value.

First, we can get the custom field value by using the below code.

 <?php $custom_field_value= get_post_meta( get_the_ID(), 'generic-name', true ); ?>

This $custom_field_value return the value of 'generic-name' field.

By using that value we can form WP_Query.

$the_query = new WP_Query( array(
      'posts_per_page'=>9,
      'post_type'=>'brand-name',
      'order'   => 'ASC',
      'meta_query' => array(
       array(
            'key' => 'generic-name',
            'value' => $custom_field_value
       ), 
    ), 
    'paged' => get_query_var('paged') ? get_query_var('paged') : 1) 
  );

Thanks.