public partial class Window1 : Window
{
    
    public static RoutedUICommand FreezeColumnCommand = new RoutedUICommand();

    public Window1()
    {
        InitializeComponent();
        //GetData connects to the database and returns the data in a table.
        AdventureWorksLT2008DataSet.SalesOrderDetailDataTable dt = GetData();

        DG1.DataContext = dt;
    }

private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
    {
       //Get the column header that started the command and move that column left to freeze it.
       System.Windows.Controls.Primitives.DataGridColumnHeader header = (System.Windows.Controls.Primitives.DataGridColumnHeader)e.OriginalSource;
       if (header.Column.IsFrozen ==true)
       {
           return;
       }
       else
       {
           header.Column.DisplayIndex = DG1.FrozenColumnCount;
           DG1.FrozenColumnCount++;
       }
    }
}