ACF acf/update_value filter usage

The ACF acf/update_value filter is used to modify the value of a specific field before it is saved to the database. This filter can be useful in various scenarios where you need to manipulate the field value before it is stored.

Here’s an example of how you can use the acf/update_value filter to modify the value of a text field before it is saved:

function wpsnippets_modify_text_field_value($value, $post_id, $field) {
    // Check if the field key matches the field you want to modify
    if ($field['key'] === 'field_1234567890') {
        // Modify the value as needed
        $value = 'Modified: ' . $value;
    }

    return $value;
}
add_filter('acf/update_value', 'wpsnippets_modify_text_field_value', 10, 3);

In this example, we define a custom function wpsnippets_modify_text_field_value that accepts three parameters: $value, $post_id, and $field. The $value parameter represents the current value of the field, $post_id is the ID of the post being saved, and $field contains information about the field being updated.

Inside the function, we check if the $field['key'] matches the key of the field we want to modify. If it matches, we prepend the value with the string “Modified: “.

Finally, we use the add_filter function to hook our custom function to the acf/update_value filter with a priority of 10 and a total of 3 parameters.

This code snippet can be useful when you want to perform custom modifications on the value of a specific ACF field before it is saved to the database. For example, you can use it to sanitize user input, format the value in a specific way, or perform calculations based on other field values.

Examples

Example 1: Modifying a field value before it is saved

This use case demonstrates how to use the acf/update_value filter to modify a field value before it is saved to the database. In this example, we will modify the value of a text field by appending a string to it.

add_filter('acf/update_value', 'wpsnippets_modify_field_value', 10, 3);
function wpsnippets_modify_field_value($value, $post_id, $field) {
    if ($field['type'] === 'text') {
        $value .= ' (modified)';
    }
    return $value;
}

Explanation: The acf/update_value filter is used to modify the value of a field before it is saved. In this example, we check if the field type is “text” and if so, append the string ” (modified)” to the value. The modified value is then returned.

Example 2: Restricting field value modification based on user role

This use case demonstrates how to use the acf/update_value filter to restrict the modification of a field value based on the user’s role. In this example, we only allow users with the “editor” role to modify a specific field.

add_filter('acf/update_value', 'wpsnippets_restrict_field_modification', 10, 3);
function wpsnippets_restrict_field_modification($value, $post_id, $field) {
    $allowed_roles = array('editor');
    $user = wp_get_current_user();
    if (in_array('editor', $user->roles) && $field['name'] === 'my_field') {
        return $value;
    }
    return $field['value'];
}

Explanation: The acf/update_value filter is used to restrict the modification of a field value based on the user’s role. In this example, we check if the user has the “editor” role and if the field name is “my_field”. If both conditions are met, the original value is returned. Otherwise, the field value is reset to its original value.

Example 3: Modifying a specific field value based on a condition

This use case demonstrates how to use the acf/update_value filter to modify a specific field value based on a condition. In this example, we check if another field has a specific value and modify the target field accordingly.

add_filter('acf/update_value', 'wpsnippets_modify_field_based_on_condition', 10, 3);
function wpsnippets_modify_field_based_on_condition($value, $post_id, $field) {
    $condition_field = get_field('condition_field', $post_id);
    if ($condition_field === 'specific_value' && $field['name'] === 'target_field') {
        $value = 'Modified value';
    }
    return $value;
}

Explanation: The acf/update_value filter is used to modify a specific field value based on a condition. In this example, we retrieve the value of another field named “conditionfield” using the get_field() function. If the condition field has the value “specificvalue” and the current field is “target_field”, we modify the value to “Modified value”. The modified value is then returned.