gridview

Question

 i can able to create new row with the help of this code

DataTable Dt = new DataTable(); //Define In Globle

            DataRow dr = Dt.NewRow();

            dr["ColumnName"] = "Your Value";

            Dt.Rows.Add(dr);

            grid.DataSource = Dt;

            grid.DataBind()
But  i want to have test box to the newly created row and the text which i have entered the that should be stored in my datbase ;
please help me