wpmu_signup_user_notification

wpmu_signup_user_notification – 當新使用者的賬戶被建立時，此函式向其傳送電子郵件通知。

當使用者註冊一個新的使用者帳戶時，向他們傳送一封確認請求的電子郵件（沒有同時註冊一個網站 同時）。在點選確認連結之前，該使用者賬戶將不會被啟用。

這是在沒有申請新網站時使用的通知功能。

過濾器 {@see ‘wpmu_signup_user_notification’} 可以繞過這個功能，或者用你自己的通知行為替換它。

過濾{@see ‘wpmu_signup_user_notification_email’}和{@see ‘wpmu_signup_user_notification_subject’}來改變傳送給使用者的郵件內容和主題。
和主題行，以改變傳送給新註冊使用者的電子郵件的內容。

function wpmu_signup_user_notification( $user_login, $user_email, $key, $meta = array() ) {
	/**
	 * Filters whether to bypass the email notification for new user sign-up.
	 *
	 * @since MU (3.0.0)
	 *
	 * @param string $user_login User login name.
	 * @param string $user_email User email address.
	 * @param string $key        Activation key created in wpmu_signup_user().
	 * @param array  $meta       Signup meta data. Default empty array.
	 */
	if ( ! apply_filters( 'wpmu_signup_user_notification', $user_login, $user_email, $key, $meta ) ) {
		return false;
	}

	$user            = get_user_by( 'login', $user_login );
	$switched_locale = switch_to_locale( get_user_locale( $user ) );

	// Send email with activation link.
	$admin_email = get_site_option( 'admin_email' );

	if ( '' === $admin_email ) {
		$admin_email = 'support@' . wp_parse_url( network_home_url(), PHP_URL_HOST );
	}

	$from_name       = ( '' !== get_site_option( 'site_name' ) ) ? esc_html( get_site_option( 'site_name' ) ) : 'WordPress';
	$message_headers = "From: "{$from_name}" <{$admin_email}>n" . 'Content-Type: text/plain; charset="' . get_option( 'blog_charset' ) . ""n";
	$message         = sprintf(
		/**
		 * Filters the content of the notification email for new user sign-up.
		 *
		 * Content should be formatted for transmission via wp_mail().
		 *
		 * @since MU (3.0.0)
		 *
		 * @param string $content    Content of the notification email.
		 * @param string $user_login User login name.
		 * @param string $user_email User email address.
		 * @param string $key        Activation key created in wpmu_signup_user().
		 * @param array  $meta       Signup meta data. Default empty array.
		 */
		apply_filters(
			'wpmu_signup_user_notification_email',
			/* translators: New user notification email. %s: Activation URL. */
			__( "To activate your user, please click the following link:nn%snnAfter you activate, you will receive *another email* with your login." ),
			$user_login,
			$user_email,
			$key,
			$meta
		),
		site_url( "wp-activate.php?key=$key" )
	);

	$subject = sprintf(
		/**
		 * Filters the subject of the notification email of new user signup.
		 *
		 * @since MU (3.0.0)
		 *
		 * @param string $subject    Subject of the notification email.
		 * @param string $user_login User login name.
		 * @param string $user_email User email address.
		 * @param string $key        Activation key created in wpmu_signup_user().
		 * @param array  $meta       Signup meta data. Default empty array.
		 */
		apply_filters(
			'wpmu_signup_user_notification_subject',
			/* translators: New user notification email subject. 1: Network title, 2: New user login. */
			_x( '[%1$s] Activate %2$s', 'New user notification email subject' ),
			$user_login,
			$user_email,
			$key,
			$meta
		),
		$from_name,
		$user_login
	);

	wp_mail( $user_email, wp_specialchars_decode( $subject ), $message, $message_headers );

	if ( $switched_locale ) {
		restore_previous_locale();
	}

	return true;
}