Wordpress'add_post_meta' - 在手动打开帖子并“更新”后，数据不会显示在页面上

Question

I'm using PHP automation to create new Wordpress posts (with wp_insert_post). I'm also using 'Simple Fields' to add additional meta fields for displaying on the front end.

My code creates the Wordpress post, keeps the post ID in a variable and then goes on to add the required meta data immediately afterwards.

Trimming all the other clutter, this is my process:

// Insert the post into the database and return the post ID
$post_id = wp_insert_post( $my_post );

// Add '$price' to relevant meta field
update_post_meta($post_id, '_simple_fields_fieldGroupID_1_fieldID_4_numInSet_0', $price);

This works fine, when I check the database, the 'price' meta field has the correct information inserted.

The problems starts when I try to extract it using:

echo simple_fields_value("price", $post->ID);

The code works - But the only way I can get it to pull the data is to log into the Wordpress admin, open the post for editing and then hit 'Update'.

Providing I open every post and hit 'Update', there's not a problem with my code... it does everything as expected.

My question is, what is the 'Update' button doing that I'm not? I've tried using 'wp_update_post' to re-open the post and save after the meta data is added to see if that helped, but it doesn't.

// Open and update post to ensure meta data saves correctly
$update_post = array(
  'ID'           => $post_id,
  'post_title'   => $title
);

// Update the post into the database
wp_update_post($update_post);

Your help on this would be much appreciated,

Answer 1

It looks like you are using the Simple Fields Plugin. I have never personally used this plugin, however I had a quick look and it looks like the plugin runs a few extra things on the save of the post. Here is one of the queries it uses for some sort of cacheing :

// Save info about the fact that this post have been saved. This info is used to determine if a post should get default values or not.
        update_post_meta($post_id, "_simple_fields_been_saved", "1");

Since you are inserting this meta value manually, I would recommend you use the native wordpress get_post_meta function to call the value, your query should look something like this:

get_post_meta($post->ID, "_simple_fields_fieldGroupID_1_fieldID_4_numInSet_0");