Create a WordPress Welcome Message for Users

// Create a welcome message shortcode
function d4tw_welcome_msg () {
$current_user = wp_get_current_user(); //get the current user info
if ( is_user_logged_in () && ( $current_user->user_firstname ) ) { //this will run if user is logged in and has a first name registered
return '<p>Welcome back ' . $current_user->user_firstname . '. Thank you for shopping!'; //return the message
}
elseif ( is_user_logged_in () && ( ! $current_user->user_firstname ) ) { //this will run if user is logged in with no first name registered
return '<p>Welcome back ' . $current_user->nickname . '. Thank you for shopping!'; //run the message
}
else {
return 'Welcome, guest! Click <a href = "/my-account/">here</a> to create an account or login.'; //this will run for guest users
}
}
add_shortcode('welcome_message', 'd4tw_welcome_msg');