In an earlier post I mentioned I am using the “OnTransactionCommiting” on the Diagram class to implement some logic (generating WSDL) for the DSL we are writing. My remark at that point was that the event is triggered a lot and therefore might not be the best place to implement time consuming logic. At that point I didn’t pay a lot of attention to the “TransactionCommitEventArgs” parameter of the event. After some further investigation I found out that the “Transaction” (that can be reached through the TransactionCommitedEventArgs) has a logical name that “indicates” what is happening in the diagram and what (user) action triggered this event.

For example, when changing the value of a property named “WSDLDescription” in the diagram, the name of the Transaction is “Set WSDLDescription”, when first loading a diagram the name of the Transaction is “LoadDocData”, etc. The code snippet below gives you an idea how to limit unnecessary (custom) code executions that you might implement in the “OnTransactionCommiting”.

public override void OnTransactionCommitting(TransactionCommitEventArgs e)
{
   base.OnTransactionCommitting(e);

   if ( e.Transaction.Name.ToUpper() == "SET WSDLDESCRIPTION")
   {

      //only execute in case of a change in the WSDLDescription property
      DoStuff();
   }
}

This actually means that I have much more control than I initially thought and therefore makes the “OnTransactionCommiting” a usefull event to implement some other logic too.

To be continued…