public void AddmainbillRow(mainbillRow row) {
     this.Rows.Add(row);
 }
 public void RemovemainbillRow(mainbillRow row) {
     this.Rows.Remove(row);
 }
 public mainbillRowChangeEvent(mainbillRow row, global::System.Data.DataRowAction action) {
     this.eventRow = row;
     this.eventAction = action;
 }