public void AddzbillRow(zbillRow row) {
     this.Rows.Add(row);
 }
 public void RemovezbillRow(zbillRow row) {
     this.Rows.Remove(row);
 }
 public zbillRowChangeEvent(zbillRow row, global::System.Data.DataRowAction action) {
     this.eventRow = row;
     this.eventAction = action;
 }