How to get Woocommerce Variation ID?

Question

I\'ve already had this code on functions.php

This code is to add a new field on each product variation to have datetime input field, so variations would automaticall

Answer 1

In WooCommerce 3+, it's $variation->get_id() from $variation function argument, which is an instance of the WC_Product_Variation.

The method get_id() is inherited from WC_Data class.

So in your code it should be instead:

'id' => '_text_field_date_expire[' . $variation->get_id() . ']',

Since WooCommerce 3, All WC_Product properties can't be accessed directly. Instead, you need to use the available methods.

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Also in your hooked function save_variation_settings_fields() you are declaring 2 arguments, so there is one missing. It should be:

//Save New Fields for Variation// Save Variation Settings
add_action( 'woocommerce_save_product_variation', 'save_variation_settings_fields', 10, 2 );

function save_variation_settings_fields( $variation_id, $i ) {
    // Text Field
    $text_field = $_POST['_text_field_date_expire'][ $variation_id ];
    if( ! empty( $text_field ) ) {
        update_post_meta( $variation_id, '_text_field_date_expire', esc_attr( $text_field ) );
    }
}

See the source code for woocommerce_save_product_variation action hook