Alvin,
>i would like to show an html file if the user clicks a command button.
>
>is there a command in vfp for this?
Go to my website listed below, download the SpyIn.zip file, there's code in there to show you how to use the ShellExecute() API call to launch the default browser with a web URL or local file, or to launch the default email system with a mailto: tag. It's really pretty painless, the dfwinapi.vcx has a class wrapper around the API call to make it even easier to use.