VS 2010 Merging / union two data tables with same columns

Hi there...

I'm still learning about data tables so I hope somebody can assist....and assume I know nothing :)

I have a dataset with a datatable defined. I'll just say Dataset1 and datatable1 with all the columns made in the dataset.

I create a new instance of datatable1 called "dtsale" and fill it with data using an SQL query.

I create a new instance of datatable1 called "dtcanc" and fill it with data using an SQL query.

I then do some calculations in .NET on a column in the datatable in a column called STATUS

eg.
dtsale.Columns("STATUS").Expression = "'SALE'"
dtcanc.Columns("STATUS").Expression = "'CANC'"

.. I have these two tables, with same columns.. I want to do a merge / union so one set of data is placed below the other. I then put the datatable into Excel.

I can get it into Excel no problem using dtsale or dtcanc but not the two together.

below is code I have tried but it's not right.

Any help is appreciated. Doing the UNION in SQL before I put into a datatable isn't an option for me on this occasion due to some other calculations I'm doing before the merge.

Kind Regards