save records in dataGridView without doing tabout

Question

I have a dataGridView and when I do some modifcations I want to get those modified records.
For that I'm using this command
DataTable dt = ((DataTable)this.dataGridView1.DataSource).GetChanges(DataRowState.Added)

But the problem is when I add a row press save button without doing tabout..that record is not going to the database. Can anyone tell me how to overcome this issue.