WooCommerce Custom Fields for Variations

custom-fields-for-variations.php

<?php
//Display Fields
add_action( 'woocommerce_product_after_variable_attributes', 'variable_fields', 10, 3 );
//Save variation fields
add_action( 'woocommerce_save_product_variation', 'save_variable_fields', 10, 2 );


function variable_fields( $loop, $variation_data, $variation ) {
    // Text Field
    $text_field = get_post_meta( $variation->ID, '_text_field', true ); 
    woocommerce_wp_text_input( 
        array( 
            'id'          => 'text_field['.$variation->ID.']', 
            'label'       => __( 'My Text Field', 'woocommerce' ), 
            'placeholder' => __( 'placeholder text', 'woocommerce' ),
            'desc_tip'    => 'true',
            'description' => __( 'Enter custom value here.', 'woocommerce' ),
            'value'       => $text_field
        )
    );
    // Number Field
    $number_field = get_post_meta( $variation->ID, '_number_field', true ); 
    woocommerce_wp_text_input( 
        array( 
            'id'          => 'number_field['.$variation->ID.']', 
            'label'       => __( 'My Number Field', 'woocommerce' ), 
            'desc_tip'    => 'true',
            'type'		  => 'number', 	
            'description' => __( 'Enter custom number here.', 'woocommerce' ),
            'value'       => $number_field,
            'custom_attributes' => array(
                'step' 	=> 'any',
                'min'	=> '0'
            ) 
        )
    );
    // Textarea
    $textarea = get_post_meta( $variation->ID, '_textarea', true ); 
    woocommerce_wp_textarea_input( 
        array( 
            'id'          => 'textarea['.$variation->ID.']', 
            'label'       => __( 'My Textarea', 'woocommerce' ), 
            'desc_tip'    => 'true', 
            'description' => __( 'Enter custom value here.', 'woocommerce' ),
            'value'       => $textarea,
        )
    );
    // Select
    $select = get_post_meta( $variation->ID, '_select', true ); 
    woocommerce_wp_select( 
    array( 
        'id'          => 'select['.$variation->ID.']', 
        'label'       => __( 'Select', 'woocommerce' ), 
        'description' => __( 'Choose a value.', 'woocommerce' ),
        'value'       => $select,
        'options' => array(
            'one'   => __( 'Option 1', 'woocommerce' ),
            'two'   => __( 'Option 2', 'woocommerce' ),
            'three' => __( 'Option 3', 'woocommerce' )
            )
        )
    );
    // Checkbox
    $checkbox = get_post_meta( $variation->ID, '_checkbox', true ); 
    woocommerce_wp_checkbox( 
    array( 
        'id'            => 'checkbox['.$variation->ID.']', 
        'label'         => __('Check', 'woocommerce' ), 
        'description'   => __( 'Check me!', 'woocommerce' ),
        'value'         => $checkbox, 
        )
    );
}

/**
 * Save custom field values for variations
 *
 */
function save_variable_fields( $variation_id ) {

    // Text Field
    if ( isset( $_POST['text_field'][ $variation_id ] ) ) {
        $text_field_value = sanitize_text_field( $_POST['text_field'][ $variation_id ] );
        update_post_meta( $variation_id, '_text_field', $text_field_value );
    }
    
    // Number Field
    if ( isset( $_POST['number_field'][ $variation_id ] ) ) {
        $number_field_value = absint( $_POST['number_field'][ $variation_id ] );
        update_post_meta( $variation_id, '_number_field', $number_field_value );
    }
    
    // Textarea
    if ( isset( $_POST['textarea'][ $variation_id ] ) ) {
        $textarea_value = sanitize_textarea_field( $_POST['textarea'][ $variation_id ] );
        update_post_meta( $variation_id, '_textarea', $textarea_value );
    }
    
    // Select
    if ( isset( $_POST['select'][ $variation_id ] ) ) {
        $select_value = sanitize_key( $_POST['select'][ $variation_id ] );
        update_post_meta( $variation_id, '_select', $select_value );
    }
    
    // Checkbox
    $checkbox_value = isset( $_POST['checkbox'][ $variation_id ] ) ? 'yes' : 'no';
    update_post_meta( $variation_id, '_checkbox', $checkbox_value );
        
}