The get_registered_meta_keys() WordPress PHP function retrieves a list of registered metadata arguments for an object type, keyed by their meta keys.
Usage
get_registered_meta_keys( $object_type, $object_subtype = '' );
Parameters
$object_type(string) (required) – Type of object metadata is for. Accepts ‘post’, ‘comment’, ‘term’, ‘user’, or any other object type with an associated meta table.$object_subtype(string) (optional) – The subtype of the object type. Default: ”
More information
See WordPress Developer Resources: get_registered_meta_keys()
Examples
Get registered meta keys for posts
In this example, we retrieve the registered meta keys for posts.
// Get the registered meta keys for 'post' object type
$registered_meta_keys = get_registered_meta_keys( 'post' );
// Output the registered meta keys
foreach ( $registered_meta_keys as $key => $value ) {
echo "Key: " . $key . "\n";
}
Get registered meta keys for a custom post type
In this example, we retrieve the registered meta keys for a custom post type called ‘product’.
// Get the registered meta keys for 'post' object type with 'product' subtype
$registered_meta_keys = get_registered_meta_keys( 'post', 'product' );
// Output the registered meta keys
foreach ( $registered_meta_keys as $key => $value ) {
echo "Key: " . $key . "\n";
}
Get registered meta keys for users
In this example, we retrieve the registered meta keys for users.
// Get the registered meta keys for 'user' object type
$registered_meta_keys = get_registered_meta_keys( 'user' );
// Output the registered meta keys
foreach ( $registered_meta_keys as $key => $value ) {
echo "Key: " . $key . "\n";
}
Get registered meta keys for terms
In this example, we retrieve the registered meta keys for terms.
// Get the registered meta keys for 'term' object type
$registered_meta_keys = get_registered_meta_keys( 'term' );
// Output the registered meta keys
foreach ( $registered_meta_keys as $key => $value ) {
echo "Key: " . $key . "\n";
}
Get registered meta keys for comments
In this example, we retrieve the registered meta keys for comments.
// Get the registered meta keys for 'comment' object type
$registered_meta_keys = get_registered_meta_keys( 'comment' );
// Output the registered meta keys
foreach ( $registered_meta_keys as $key => $value ) {
echo "Key: " . $key . "\n";
}