How to get difference between two DataTables

Question

I have these two datatables and I want to get the difference between them. Here is an example:

Table1
-------------------------
ID  |   Name 
---------------         


        

Answer 1

Try this

DataTable dtmismatch = Table1.AsEnumerable().Except(Table2.AsEnumerable(), DataRowComparer.Default).CopyToDataTable<DataRow>();

Answer 2

I just went through this and wanted to share my findings. For my application it is a data sync mechanism, but i think you will see how this applies to the original question.

In my case, I had a DataTable that represented my last data upload and sometime in the future, I need to get the current state of the data and only upload the differences.

//  get the Current state of the data
DataTable dtCurrent = GetCurrentData();

//  get the Last uploaded data
DataTable dtLast = GetLastUploadData();
dtLast.AcceptChanges();

//  the table meant to hold only the differences
DataTable dtChanges = null;

//  merge the Current DataTable into the Last DataTable, 
//  with preserve changes set to TRUE
dtLast.Merge(dtCurrent, true);

//  invoke GetChanges() with DataRowState.Unchanged
//    !! this is the key !!
//    the rows with RowState == DataRowState.Unchanged 
//    are the differences between the 2 tables
dtChanges = dtLast.GetChanges(DataRowState.Unchanged);

I hope this helps. I fought with this for a few hours, and found lots of false-leads on the interwebz, and ended up comparing RowStates after merging a few different ways