WooCommerce注册表单自定义生日字段的添加与正确保存实践

/**
 * 将自定义生日字段添加到WooCommerce“我的账户”注册表单
 */
add_action( 'woocommerce_register_form_start', 'add_custom_birthday_fields_to_registration_form' );
function add_custom_birthday_fields_to_registration_form() {
    ?>
    <p class="form-row form-row-first-name">
        <label for="billing_first_name"><?php _e( 'First name', 'woocommerce' ); ?><span class="required">*</span></label>
        <input type="text" class="input-text" name="billing_first_name" id="billing_first_name" value="<?php if ( ! empty( $_POST['billing_first_name'] ) ) esc_attr_e( $_POST['billing_first_name'] ); ?>" />
    </p>

    <p class="form-row form-row-last-name">
        <label for="billing_last_name"><?php _e( 'Last name', 'woocommerce' ); ?><span class="required">*</span></label>
        <input type="text" class="input-text" name="billing_last_name" id="billing_last_name" value="<?php if ( ! empty( $_POST['billing_last_name'] ) ) esc_attr_e( $_POST['billing_last_name'] ); ?>" />
    </p>

    <table class="form-table">
        <tr>
            <th><label for="birth-date-day"><?php echo __( 'Birthday' ); ?></label></th>
            <td>
                <select id="birth-date-day" name="birthday[day]">
                    <option selected="selected" value=""><?php echo __( 'Day' ); ?></option><?php
                    for( $i = 1; $i <= 31; $i++ ) {
                        printf( '<option value="%1$s">%1$s</option>', $i );
                    } ?>
                </select>

                <select id="birth-date-month" name="birthday[month]">
                    <option selected="selected" value=""><?php echo __( 'Month' ); ?></option>
                    <option value="1"><?php _e( 'January' ); ?></option>
                    <option value="2"><?php _e( 'February' ); ?></option>
                    <option value="3"><?php _e( 'March' ); ?></option>
                    <option value="4"><?php _e( 'April' ); ?></option>
                    <option value="5"><?php _e( 'May' ); ?></option>
                    <option value="6"><?php _e( 'June' ); ?></option>
                    <option value="7"><?php _e( 'July' ); ?></option>
                    <option value="8"><?php _e( 'August' ); ?></option>
                    <option value="9"><?php _e( 'September' ); ?></option>
                    <option value="10"><?php _e( 'October' ); ?></option>
                    <option value="11"><?php _e( 'November' ); ?></option>
                    <option value="12"><?php _e( 'December' ); ?></option>
                </select>

                <select id="birth-date-year" name="birthday[year]">
                    <option selected="selected" value=""><?php echo __( 'Year' ); ?></option><?php
                    // 从当前年份减去14年（例如，最小年龄限制）到99年（例如，最大年龄限制）
                    for( $i = date("Y") - 14; $i >= date("Y") - 99 ; $i-- ) {
                        printf( '<option value="%1$s">%1$s</option>', $i );
                    } ?>
                </select>
            </td>
        </tr>
    </table>
    <?php
}

/**
 * 验证WooCommerce注册表单中的自定义字段
 */
add_action( 'woocommerce_register_post', 'validate_custom_registration_fields', 10, 3 );
function validate_custom_registration_fields( $username, $email, $validation_errors ) {
    if( isset( $_POST['billing_first_name'] ) && empty( $_POST['billing_first_name'] ) ) {
        $validation_errors->add( 'billing_first_name_error', __( '<strong>Error</strong>: First name is required!', 'woocommerce' ) );
    }

    if( isset( $_POST['billing_last_name'] ) && empty( $_POST['billing_last_name'] ) ) {
        $validation_errors->add( 'billing_last_name_error', __( '<strong>Error</strong>: Last name is required!.', 'woocommerce' ) );
    }

    // 检查生日字段的每个部分是否都已选择
    if ( isset( $_POST['birthday'] ) ) {
        $birthday_data = $_POST['birthday'];
        if ( empty( $birthday_data['day'] ) || empty( $birthday_data['month'] ) || empty( $birthday_data['year'] ) ) {
            $validation_errors->add( 'birthday_error', __( '<strong>Error</strong>: Birthday is required!.', 'woocommerce' ) );
        }
        // 进一步的日期有效性检查，例如闰年、月份天数等，可以根据需要添加
        // 例如：if ( ! checkdate( $birthday_data['month'], $birthday_data['day'], $birthday_data['year'] ) ) { ... }
    } else {
        $validation_errors->add( 'birthday_error', __( '<strong>Error</strong>: Birthday is required!.', 'woocommerce' ) );
    }

    return $validation_errors;
}

/**
 * 保存WooCommerce注册表单中的额外字段
 */
add_action( 'woocommerce_created_customer', 'save_custom_registration_fields' );
function save_custom_registration_fields( $customer_id ) {
    if( isset( $_POST['billing_first_name'] ) ) {
        update_user_meta( $customer_id, 'first_name', sanitize_text_field( $_POST['billing_first_name'] ) );
        update_user_meta( $customer_id, 'billing_first_name', sanitize_text_field( $_POST['billing_first_name'] ) );
    }

    if( isset( $_POST['billing_last_name'] ) ) {
        update_user_meta( $customer_id, 'last_name', sanitize_text_field( $_POST['billing_last_name'] ) );
        update_user_meta( $customer_id, 'billing_last_name', sanitize_text_field( $_POST['billing_last_name'] ) );
    }

    if( isset( $_POST['birthday'] ) ) {
        $birthday_data = $_POST['birthday'];

        // 确保所有部分都存在且非空
        if ( ! empty( $birthday_data['day'] ) && ! empty( $birthday_data['month'] ) && ! empty( $birthday_data['year'] ) ) {
            // 将日、月、年组合成一个可被 strtotime 解析的日期字符串
            // 例如：'1-1-2000' (日-月-年)
            $birthday_string = implode( '-', array(
                absint( $birthday_data['day'] ),
                absint( $birthday_data['month'] ),
                absint( $birthday_data['year'] )
            ) );

            // 将日期字符串转换为 'YYYY-MM-DD' 标准格式
            $birthday_formatted = date( 'Y-m-d', strtotime( $birthday_string ) );

            // 保存生日到用户元数据
            update_user_meta( $customer_id, 'birthday', $birthday_formatted );
        }
    }
}