Hi there
Don't quite know if this is what you are looking for...
dataGridView1.Rows[0].SetValues("5","t","4","3");
Where the 0 is the row index.
So zero is first row.
I didn't give any real values there
you can also edit individual cells e.g.
dataGridView1[0, 0].Value = "Hi there";
Hope this helps :)