rwmb_get_value

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Overview

rwmb_get_value is a helper function which helps you get the field value.

It’s actually a wrapper of get_post_meta() function with some additions to match the way the plugin saves post meta in the database.

It also adds some additional information to the returned value (such as image info) to make it’s easier for developers.

Usage

To get field value or displaying it in your theme, copy the following code and paste it in your theme’s template file:

$value = rwmb_get_value( $field_id );
echo $value;

You can put it in the theme single.php or template-parts/content.php file, depending on your theme structure.

Arguments

The helper function rwmb_get_value accepts 3 arguments as below:

rwmb_get_value( $field_id, $args, $post_id );
Name Description
$field_id The field ID. Required.
$args Extra arguments for some field types (image, file, etc.). Optional. Can be array or a string in format param1=value1&param2=value2. See more details in field types (on the left menu, section Fields). Optional.
$post_id Post ID that custom fields are get from. Optional. If not present, current post ID is used.

Returned value

  • If the field has a single value (not multiple nor clone), then the function returns that value.
  • If the field has multiple values (multiple or clone), then the function returns an array of values.

This is an example how to display date of birth (which is a date field):

echo rwmb_get_value( 'dob' );

This is an example how to display list of interests (a checkbox_list field):

$interests = rwmb_get_value( 'interests' );
foreach ( $interests as $interest ) {
    echo $interest;
}

Depends on the field types, the returned value can be different. See more details in field types (on the left menu, section Fields).

Undefined function error

If you’re using rwmb_get_value in your theme, there may be a situation when an admin accidentally deactivate the Meta Box plugin and you will see error “Undefined function rwmb_get_value…” and your site will be broken.

To prevent this problem, a simple fix for that is adding the following code into your theme’s functions.php file:

if ( ! function_exists( 'rwmb_get_value' ) ) {
    function rwmb_get_value( $key, $args = '', $post_id = null ) {
        return false;
    }
}