string strNow = DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss", System.Globalization.DateTimeFormatInfo.InvariantInfo);
//...
SqlDataAdapter vSqlDataAdapter=new SqlDataAdapter();
vSqlDataAdapter.SelectCommand = new SqlCommand("sp_MyStoredProc");
vSqlDataAdapter.SelectCommand.CommandType =CommandType.StoredProcedure;
//...
vSqlParameter= vSqlDataAdapter.SelectCommand.Parameters.Add("@ColumnToBeSetToNow", strNow);