I have 2 inputs, one for username, and one for ID.

* Username value: `<?php echo esc_attr( get_option('username') ); ?>`
* ID value: `<?php echo esc_attr( get_option('id') ); ?>`

and a division:

```
<div id="info"><?php echo esc_attr( get_option('username') ); ?></div>

```

I want a PHP function to echo `<?php echo esc_attr( get_option('ID') ); ?>` in div#info ONLY IF the username field is not filled by the user.

Thank you.

P.S: Apologize if similar topics already exist, but I have looked'em up and couldn't find a straight answer for such a beginner.