InfoPath Dev

Hello everyone, I want to merge my current solution from VS2003+InfoPath2003(c# code background) to VS2005+InfoPath2007. Can anybody tell me? Any idea would be greatly appreciated!

Thanks Shiva very much. But now I encounter another problem. I have input some data into InfoPath form's XML file. Then, how to save the file?  

Thanks Shiva. It is a great help.

Hi everyone, Currently I get the data from database, and want to insert it into some of my InfoPath project's existing XML files. But I don't know how to do load the existing XML files so that I could do some operations on them. Any idea would be greatly appreciated!