By default, commands are accessible whenever the form they are defined for is open. You can control whether a command is accessible by using the enable command and disable command statements. When command is disabled, it cannot be executed. It will also appear disabled on any menu or toolbar that displays it.
You can use the hide command and show command statements to control whether a command is visible. When a command is hidden, it is automatically removed from any menus or toolbars that display it.