Thanks swathip's reply.
But my design is:
I add a XML file to Infopath project as datasource of Text Box controls. And I add some codes for updating this XML file by get Values from Database. Then I compile this project and get a .xsn file. Now when I open this Infopath Form Templete, I will get an exception and it cannot update this XML file.
I realy want to implement the Infopath offline function.
But I think it is unavailable. Because after I update this XML file included in form, I need to recompile this project. I mean we cannot modify those files included in form (.xsn file)
Correct?????