Document GUID

[drobertsY4GL3]

My plugin currently uses the document name + object handle as an identifier when saving records to an SQL database. I would like to use a more robust document id than the name, so that the document is seen as the same, even if it is moved to a different location, or if the file is renamed. 

I have tried using the document hash, but this changes based on where the document is located. Same with the document.Database.FingerprintGuid.

Would creating a custom document property like myDocumentGUID be the best way to go?

[norman.yuan]

You might consider embed an GUID value in the drawing's named dictionary (of course create your own named Dictionary underneath the drawing's named dictionary).

[daniel_cadext · Accepted solution]

DWGPROPS, summary section, keywords or comments, or custom area is easy to read
XDATA attached to the 0 layer would be easy to access as well

In ARX FingerprintGuid has a set and get, maybe you can assign the GUID, but then it might be a race between who sets it first, you or autocad.

I always thought FingerprintGuid never changed... odd

[drobertsY4GL3 · Accepted solution]

Thank you daniel and norman. Your suggestions worked great!

Below is the implementation I used.

ViewModel:

 // Check document for GUID custom propery and assign if missing.
documentGUID = Utilities.GetDocumentGUID();
if(documentGUID == null)
{
    Utilities.SetDocumentGUID();
    var customizationSection = new Autodesk.AutoCAD.Customization.CustomizationSection();
    // Save the document after assigning a custom GUID property.
    customizationSection.Save();
    documentGUID = Utilities.GetDocumentGUID();
}

Helper Methods:

 public static string GetDocumentGUID()
{
    // Check if custom property exists.
    var document = Application.DocumentManager.MdiActiveDocument;

    System.Collections.IDictionaryEnumerator customProperties = document.Database.SummaryInfo.CustomProperties;

    while(customProperties.MoveNext())
    {
        var key = customProperties.Key.ToString();
        if(key == "DOCUMENT_GUID")
        {
            return customProperties.Value.ToString();
        }
    }

    return null;
}

 public static void SetDocumentGUID()
{
    // Create custom propery
    var document = Application.DocumentManager.MdiActiveDocument;
    var infoBuilder = new DatabaseSummaryInfoBuilder();
    var GUID = System.Guid.NewGuid().ToString();
    infoBuilder.CustomPropertyTable.Add("DOCUMENT_GUID", GUID);

    using (DocumentLock docLock = document.LockDocument())
    {
        document.Database.SummaryInfo = infoBuilder.ToDatabaseSummaryInfo(); 
    }
}

More info on creating custom properties:
https://forums.autodesk.com/t5/net/create-document-custom-property/td-p/11763555