using System.Data.SqlServerCe;

public void Insert()
        {
            using (SqlCeConnection ceConn = new SqlCeConnection("Data Source=SQLCEDB.sdf"))
            {
                using (SqlCeCommand ceComm = new SqlCeCommand
                    ("INSERT INTO TABLENAME (FIELD1,FIELD2,FIELD3) VALUES (@VAL1,@VAL2,@VAL3)"))
                {
                    ceComm.Parameters.Add("@VAL1", System.Data.SqlDbType.NVarChar).Value = "VAL1";
                    ceComm.Parameters.Add("@VAL2", System.Data.SqlDbType.NVarChar).Value = "VAL2";
                    ceComm.Parameters.Add("@VAL3", System.Data.SqlDbType.NVarChar).Value = "VAL3";
                    ceComm.Connection = ceConn;
                    ceComm.CommandType = System.Data.CommandType.Text;
                    ceComm.ExecuteNonQuery();
                }
            }
        }