PreviewKeyDown(object sender, KeyEventArgs e)
{
  DataGrid grid = (DataGrid)sender;
 
  if (e.Key == Key.Enter || e.Key == Key.Return)
  {
    // get the selected row 

  var selectedRow = grid.ItemContainerGenerator.ContainerFromItem(grid.SelectedItem)as DataGridRow;
 
    // selectedRow can be null due to virtualization

 if (selectedRow != null)
    {
      // there should always be a selected cell   

  if (grid.SelectedCells.Count != 0)
      {
         // get the cell info        

DataGridCellInfo currentCell = grid.SelectedCells[0];
 
         // get the display index of the cell's column + 1 (for next column)       

 int columnDisplayIndex = currentCell.Column.DisplayIndex++;
 
         // if display index is valid     

   if (columnDisplayIndex < grid.Columns.Count)
         {
            // get the DataGridColumn instance from the display index       

     DataGridColumn nextColumn = grid.ColumnFromDisplayIndex(columnDisplayIndex);
 
            //

       e.Handled =true;
 
            // setting the current cell (selected, focused)       

     grid.CurrentCell =new DataGridCellInfo(grid.SelectedItem, nextColumn);
 
            // tell the grid to initialize edit mode for the current cell   

         grid.BeginEdit();
         }
      }
    }
  }
}