Sort on multiple columns in WPF datagrid

Question

How can I set up my WPF datagrid to sort on multiple columns similar to having two sortable columns, clicking on the header of the first column for a primary sort and then S

Answer 1

I hope this will help others. My solution keep the default sort functionality and allow sorting on multiple columns.

Put a sorting event on your datagrid

And now in your code behind

private void dataGridName_Sorting(object sender, DataGridSortingEventArgs e)
{
    var dgSender = (DataGrid) sender;
    var cView = CollectionViewSource.GetDefaultView(dgSender.ItemsSource);

    //Alternate between ascending/descending if the same column is clicked 
    ListSortDirection direction = ListSortDirection.Ascending;
    if (cView.SortDescriptions.FirstOrDefault().PropertyName == e.Column.SortMemberPath)
        direction = cView.SortDescriptions.FirstOrDefault().Direction == ListSortDirection.Descending ? ListSortDirection.Ascending : ListSortDirection.Descending;

    cView.SortDescriptions.Clear();
    AddSortColumn((DataGrid)sender, e.Column.SortMemberPath, direction);
    //To this point the default sort functionality is implemented

    //Now check the wanted columns and add multiple sort 
    if (e.Column.SortMemberPath == "WantedColumn")
    {
        AddSortColumn((DataGrid)sender, "SecondColumn", direction);
    }
    e.Handled = true;
}

private void AddSortColumn(DataGrid sender, string sortColumn, ListSortDirection direction)
{
    var cView = CollectionViewSource.GetDefaultView(sender.ItemsSource);
    cView.SortDescriptions.Add(new SortDescription(sortColumn, direction));
    //Add the sort arrow on the DataGridColumn
    foreach (var col in sender.Columns.Where(x => x.SortMemberPath == sortColumn))
    {
        col.SortDirection = direction;
    }
}

The sortDirection on the DataGridColumn allow showing the arrow on the grid.