We have a huge bank of legacy code written in vb6 that we're slowly porting over to dot net. One of these components that's getting shuffled over this week is our Invoice Printing functionality.
Previously this logic was written in Data Dynamics Active Reports 1.0 (COM based) and we're looking to upgrade this to Active Reports 4.2 (Dot Net 2.0). A quick plug, Active Reports is an absolutely awesome tool for designing and developing business reports. Even their COM-based 1.0 model shows a ton of insight into HOW we should be developing reporting applications.
Anyway, we're going to have to re-write some code as part of this process but the one component that would be nice to pull across is the "design" surface. This basically consists of all the controls and layouts. If we have to re-design this from scratch we're going to miss positions, fonts, etc so it's better to automate this piece if we can. Here's what it looks like...
Now, Active Reports supports a common design layout for AR2.0 to AR4.2, sort of a XML-based layout language they call RPX. If you can save a report layout into an RPX you can load it back later on. Trick is that our reports are AR1.0 and that old version uses a different binary format for saving layouts. I need to somehow upgrade these from AR1.0 to AR2.0 before I can save them into the common format.
Turns out this is easier than you'd think. The vb6 report design files are seperated into two components... a binary .DSX file and a text .DSR file. If you crack open the DSR file the first bit of "code" specifies which tool "manages" the resource. That's what the big ugly guid is. By changing this guid from AR1.0 to AR2.0 we can fake VB6 into thinking it's dealing with an AR2.0 report.
Now, when we open up the designer in vb6, we have the option to save the report layout by using the File, Save feature within the report designer. Likewise in dot net we can use the Report menu item to Load a saved layout. We've managed to save ourselves all the work in positioning, sizing, and configuring all the controls behind this active report!
Now, all this effort to avoid recreating some controls... worth it? To me it is. The problem with me redesiging these reports is that...
1. I'm not that great of a detail guy. Not bad, but not great. I'm positive I'd screw something up. And it may not be a huge deal to the first 20 stores that get this upgrade but at some point that change in field size would be a critical concern to some store. If I can avoid the issue altogether that's a good thing.
2. I get bored easy. I'd copy probably 5 controls before I'd get distracted and switched over to something else. I'll bet you it would take me a week to get this one report copied over. By converting the entire report in one pass I've moved the project to the point where I can have someone else take over the loading of data.