If u are using a database and want to save this into the database and
then display, just submitting the values page and updating the database
will help.

If u don't want to save into the database immediately then after
submitting the page , you must be having a dataset that has been binded
to the datagrid  , so you will require to add a row  in the datatable of
the dataset, and as the dataset is bound to a data grid the values will
be displayed in the datagrid.