It might be easier to just work with the higher-level DataSet, like this:

DataSet dataSet = new DataSet();

DataTable dataTable = new DataTable();


dataSet.Tables.Add(dataTable);

// Save to disk
dataSet.WriteXml(@"C:\MyDataset.xml");


// Read from disk
dataSet.ReadXml(@"C:\MyDataset.xml");


sorry its in c# but logic is kinda the same