Use the FormViewUpdatedEventArgs.AffectedRows property to determine the number of records affected by the update operation. This property is commonly used to verify that the correct number of records was updated in the following situations:

• Verify that only a single record was updated. Sometimes an improperly written update statement can update multiple records.

• Verify that a record was updated when an error occurs during the update operation that does not raise an exception.

• Verify that a record was updated when a data source control that supports conflict detection (optimistic concurrency checking), such as the System.Web.UI.WebControls.SqlDataSource and System.Web.UI.WebControls.ObjectDataSource controls, has its SqlDataSource.ConflictDetection property set to the ConflictOptions.CompareAllValues enumeration value. Under this setting, a record that has been modified by another user concurrently might not be updated.