These code snippets enable you to add the author box only when a custom field has been added as well.
The author box is added in the default position after single posts.
The code also enables you to remove the author box from single posts when a custom field has been added if you have the user settings configured to display the author box on all single posts.
You can add your own custom field or use the custom field added by any theme or plugin.
Here’s the code for logged in members: