VS2012 -> Custom editor and Dirty state

Hi,

I am implementing a custom editor for an own file extension. For the dirty handling I am implementing the IPersistFileFormat.IsDirty method. This method gets periodically called by VS and updates the dirty state of my editor.

In VS 2012 this "IsDirty" method gets called only every five seconds which is too slow.

Is there a mechanism to force VS to call this method / update the dirty state programmatically?

Thanks,

Stefan