Documents Collection (Visio)
Includes a Document object for each open document in a Microsoft Visio instance.
Remarks
To retrieve a Documents collection, use the Documents property of an Application object.
The default property of a Documents collection is Item.
If your Visual Studio solution includes the Microsoft.Office.Interop.Visio reference, this collection maps to the following types:
Microsoft.Office.Interop.Visio.IVDocuments.GetEnumerator() (to enumerate the Document objects.)
Microsoft.Office.Interop.Visio.IVDocuments (to access the collection.)