You are creating a method to validate column values of a given DataRow. You want to check column values that have been set since an edit operation was started with the DataRow.BeginEdit method. If validation succeeds, your method calls the DataRow.EndEdit method; otherwise, your method calls the DataRow.CancelEdit method. You need to choose a DataRowVersion to access the edited column values to validate.

Which DataRowVersion should you choose?

When you modify column values in a DataRow directly, the DataRow manages the column values using the Current, Default, and Original row versions. In addition to these row versions, the BeginEdit, EndEdit, and CancelEdit methods use a fourth row version called Proposed. By calling BeginEdit for a row, you can perform validation and call EndEdit to save a Proposed version to the Current change. If validation fails, you can call CancelEdit and revert the Proposed version to the previously Current version.

The Current value gives the current values for the row. This row version does not exist for rows with a RowState of Deleted.