C# - Copy DataTable from one DataSet to another

When we trying to add a DataTable (that is inside of a different DataSet) to new DataSet ds. If I add it directly, we will get the following error:

                   DataTable already belongs to another DataSet.

DataTable.Copy

use DataTable.Copy to create a copy of your data table; then insert the copy into the target DataSet:

dataSetX.Tables.Add( dataTableFromDataSetY.Table[0].Copy() );

DataSet.Merge

You could also use DataSet.Merge for this:

dataSetX.Merge(dataTableFromDataSetY); Note, however, that if you are going to use this method, you might want to make sure that your target DataSet doesn't already contain a table with the same name:

If the target DataSet doesn't contain a table by the same name, a fresh copy of the table is created inside the data set;

If a table by the same name is already in the target data set, then it will get merged with the one passed to Merge, and you end up with a mix of the two.