yaya,
There are a few ways that you can go about doing this. The most obvious
way I would think of doing this would be to use the OLE DB provider for
Excel and try to use an OleDbDataAdapter, calling Update.
If you are using a version of Excel that supports XML, then you can just
take the dataset that the grid is bound to and then save the XML contents.
If that doesn't work, then you could take the data set, and write out to
a CSV file (cycling through the rows and columns). If you want the native
Excel format, then you will have to access Excel through automation and
populate the sheet yourself.
Hope this helps.