ADO.NET 3.5 Cookbook, 2nd Edition

4.7. Accessing Deleted Rows in a DataTable

Problem

When you delete rows from a DataSet they are really marked for deletion until changes are committed by calling AcceptChanges() either directly or indirectly. You want to access the rows that you have deleted from a DataTable.

Solution

Use one of the four techniques demonstrated in this solution.

The solution fills a DataSet with the TOP 3 records from the Person.Contact table in the AdventureWorks database. The second row is deleted. The deleted row is accessed and written to the console using the following techniques:

• Iterating over the records in the DataTable, identifying the deleted rows as having their RowState property being set to DataRowState.Deleted, and accessing the original values for the deleted row using the field accessor of the DataRow that takes a second argument and specifying it as DataRowVersion.Original.

• Creating a DataView of only deleted records in the table using an overload of the DataView constructor with the row state argument set to DataViewRowState.Deleted.

• Creating a DataView based on the table and filtering only deleted records by setting the RowStateFilter property of the DataView to DataViewRowState.Deleted.

• Using the Select() method with the row state set to DataViewRowState.Deleted to get a DataRow array of deleted records from the DataTable and accessing the values for the deleted rows through their original values by specifying a row state of DataRowVersion.Original in the DataRow field accessor.

The ...