A.RowUpdated B.DataSourceChanged C.Changed D.RowChanged
A.1 B.10 C.100 D.0
A.ds.PrimaryKey.Add("ComputerID"); B.ds.PrimaryKey=newobject[]{"ComputerID"}; C.ds.PrimaryKey="ComputerID"; D.ds.PrimaryKey=newDataColumn[]{ds.Columns["ComputerID"]};