.NET COM Interop to existing running MM instance

[tss]

I'm trying to write a simple C# application that talks to MM via COM Interop.

I create an SDBApplication instance as follows:

Code: Select all

ISDBApplication app = new SDBApplicationClass();

If MM isn't running then this works fine, but if MM is running this call causes MM to become the active application and my program blocks.

I've also tried to detect the current running object but this results in an exception:

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try
{
    object app = System.Runtime.InteropServices.Marshal.GetActiveObject("SongsDB.SDBApplication");
    if (app != null)
    {
        m_app = app as ISDBApplication;
        if (m_app != null)
            return m_app;
    }
}
catch (Exception ex)
{
    MessageBox.Show(this, ex.Message);
}

The exception occurs when I call Marshal.GetActiveObject, the message is: "Operation Unavailable".

Searching the internet, I've found other similar problems like this. Apparently this means the application has not registered itself in Running Object Table (ROT).

Is there another way to get back the active MM instance? Is MM not registering itself in the ROT when its started up?

[jmaver]

What do you mean blocks?
My two line program reaches line two:

ISDBApplication app = new SDBApplicationClass();
bool isRunning = app.IsRunning;

When does it block?

[Peke]

Try To read something in
http://www.cgoakley.demon.co.uk/prog/oleaut.html

It may help.

[tss]

By "blocks" I mean my program never gets past the line:

Code: Select all

ISDBApplication app = new SDBApplicationClass();

This ONLY happens when MM is already running. When it isn't running it works fine.

[jmaver]

This doesn't happen with mine. My apps are working regardless of whether MM is already running. Do you have any scripts that run at startup for MM that maybe get run again and could be blocking it?