The Active property returns True if the document is currently being edited by the user.
Examples:
The following VBA example displays the list of all documents currently open. Modified (and unsaved) documents display an asterisk ( * ) next to their names, and the current document is marked as Current.
Sub Test()
Dim d As Document
Dim s As String
s = "List of open documents:"
For Each d In Documents
s = s & vbCr & "- " & d.Title
If d.Dirty Then s = s & "*"
If d.Active Then s = s & " (Current)"
Next d
MsgBox s
End Sub