Pass custom posted variable from a page to Woocommerce order data - php

Question

I can add a custom variable to a WooCommerce order, using code like this - but only if the code is on the product page:
<form action="<?php echo esc_url( wc_get_checkout_url() ); ?>" method="post">
<?php
$value = isset( $_POST['dogname'] ) ? sanitize_text_field( $_POST['dogname'] ) : '';
echo '<div><label>Name of Dog</label><p><input name="dogname" value="' . $value . '"></p></div>';
?> <button type="submit">Checkout</button>
</form>
But how do I add the data to the order it if I am not on the product page? I redirect the page after add to cart to a custom page. On this custom page the cart is already populated with the product . But submitting this form on the custom page - goes to checkout but does not update or add the variable to the order. How would I update the order with my custom variable from my custom page?
Maybe I need some extra code for the button to update the order on click?
What code would I use for a button - that on click would post the form values to my order, and direct to another page?

Answer 1

Here below is a way to get posted data available in checkout page and anywhere else without loosing this posted data. For that we set the posted data to a WC session variable, so this posted data is available at any moment when needed.
The form on your page (example with multiple fields):
?><form action="<?php echo esc_url( wc_get_checkout_url() ); ?>" method="post">
<?php
$dogname = isset( $_POST['dogname'] ) ? sanitize_text_field( $_POST['dogname'] ) : '';
$dogcolor = isset( $_POST['dogcolor'] ) ? sanitize_text_field( $_POST['dogcolor'] ) : '';
?>
<div><label><?php _e("Name of Dog"); ?></label><p><input name="dogname" value="<?php echo $dogname; ?>"></p></div>
<div><label><?php _e("Color of Dog"); ?></label><p><input name="dogcolor" value="<?php echo $dogcolor; ?>"></p></div>
<button class="button" type="submit" name="dog_form" value="submited"><?php _e("Checkout"); ?></button>
</form><?php
The code that set the posted data to a WC_Session variable:
// Early enable customer WC_Session
add_action( 'init', 'wc_session_enabler' );
function wc_session_enabler() {
if ( is_user_logged_in() || is_admin() )
return;
if ( isset(WC()->session) && ! WC()->session->has_session() ) {
WC()->session->set_customer_session_cookie( true );
}
}
// Set posted data in a WC session variable
add_action( 'template_redirect', 'set_custom_posted_data_to_wc_session' );
function set_custom_posted_data_to_wc_session() {
if ( is_checkout() && ! is_wc_endpoint_url() ) {
if ( isset($_POST['dog_form']) ) {
$values = array(); // Initializing
if ( isset($_POST['dogname']) && ! empty($_POST['dogname']) ) {
$values['dogname'] = sanitize_text_field($_POST['dogname']);
}
if ( isset($_POST['dogcolor']) && ! empty($_POST['dogcolor']) ) {
$values['dogcolor'] = sanitize_text_field($_POST['dogcolor']);
}
// Set data to a WC_Session variable
if ( ! empty($values) ) {
WC()->session->set('custom_data', $values);
}
}
}
}
Code goes in functions.php file of the active child theme (or active theme). Tested and works.
Then you can get that data on any function or template with:
$values = WC()->session->get('custom_data');
$dogname = isset($values['dogname']) ? $values['dogname'] : '';
$dogcolor = isset($values['dogcolor']) ? $values['dogcolor'] : '';
Save that data to order details:
// Save WC session data as custom order meta data
add_action( 'woocommerce_checkout_create_order', 'action_checkout_add_custom_order_meta', 10, 2 );
function action_checkout_add_custom_order_meta( $order, $data ) {
$values = WC()->session->get('custom_data'); // Get data from WC Session variable
if( ! empty($values) ) {
if ( isset($values['dogname']) ) {
$order->update_meta_data( '_dogname', $values['dogname'] ); // Set dog name to order details
}
if ( isset($values['dogcolor']) ) {
$order->update_meta_data( '_dogcolor', $values['dogcolor'] ); // Set dog color to order details
}
// Remove the WC_Session variable (as we don't need it anymore)
WC()->session->__unset('custom_data');
}
}
Code goes in functions.php file of the active child theme (or active theme).
Then you can get that data from The WC_Order object order using:
$order = wc_get_order( $order_id ); // If needed, get the WC_Order object from order Id
$dogname = $order->get_meta('_dogname');
$dogcolor = $order->get_meta('_dogcolor');
Like in this hooked function that will display data on "Order received" page:
add_action( 'woocommerce_thankyou', 'thankyou_display_dog_data' );
function thankyou_display_dog_data( $order_id ) {
$order = wc_get_order( $order_id ); // Get an instance of the WC_Order object
$dog_name = $order->get_meta('_dogname');
$dog_color = $order->get_meta('_dogcolor');
echo ! empty($dog_name) ? '<p>' . $dog_name .'<p>' : '';
echo ! empty($dog_color) ? '<p>' . $dog_color .'<p>' : '';
}
Tested and works on last WooCommerce version.

Answer 2

To add some more functionality to LoicTheAztec answer using his thankyou_display_dog_data function. His included action shows the function on thank you after checkout form
add_action( 'woocommerce_admin_order_data_after_shipping_address', 'thankyou_display_dog_data' ); //add to admin order data under shipping
add_action( 'woocommerce_admin_order_data_after_billing_address', 'thankyou_display_dog_data' ); //add to admin under billing - pick one or duplicate of shipping
add_action( 'woocommerce_order_details_after_order_table', 'thankyou_display_dog_data' ); //add to frontend customers my account
add_action( 'woocommerce_email_after_order_table', 'thankyou_display_dog_data', 15, 2 ); // add to emails