How to access visio drawing (.vdw - in SharePoint page) shapes in C#

Question

Hi,
I need to get all shapes (which has links to other sharepoint pages) from visio drawing published in Visio web Access webpart. I could able to get Visio web Access webpart through code and get the diagram path.
1.how to get the drawing and shapes in it from webpart?  
2, Does it require to download the drawing locally to get all shapes in it? If so, shall use interop.visio?
3. Have seen some javascript vwa API to getShapes, etc. Is it available in C#?
4. Tried with interop.visio for the drawing which is stored on drive. It gives "exception occured" while open the .vdw file. (Documents.Open(@"C:\test.vdw");
How to do this? Please guide. Environment (VS2010, SP2010, Visio 2010). thx

Answer 1

hy,
have you found a solution?
I can read a visio file VDW on a local machine with the next code, but I can't use it on SharePoint Event Receiver because it make a "System.Security.Permissions.SecurityPermission" error on the ExtractStreamToMemory.
thanks
// read in the tmp file from disk using IStorage
byte[] buffer;
intnum;
Extractor.ExtractStreamToMemory(tmpFileName,
outbuffer,
outnum);
// access the bytes read from disk as a stream
System.IO.MemoryStreammemStream =
newSystem.IO.MemoryStream(buffer);
// work with the stream as a package
System.IO.Packaging.Packagezip = System.IO.Packaging.Package.Open(memStream);
I'm sorry, I lost the source path of this code..