site.canCheckOut()

Availability 3.0
Description Determines whether Dreamweaver can perform a Check Out operation on the specified file or files.
Arguments siteOrURL
The argument must be the keyword "site", indicating that the function should act on the selection in the Site window, or the URL for a single file.
Returns A Boolean value indicating whether all of the following conditions are true:
A remote site has been defined.
If a Document window has focus, the file is part of a local site and is not already checked out; or, if the Site window has focus, one or more files or folders is selected and at least one of the selected files is not already checked out.
Check in/check out is turned on.