WPF: Binding source is string with path to property

public partial class MyClass1 : Window
{
     public MyClass2 MyClass2Object { get; set; }

     public MyClass1()
     {
          InitializeComponent();
          MyClass2Object = new MyClass2();
          Binding binding = new Binding();
          binding.Source = MyClass2Object;
          binding.Path = new PropertyPath("StringVar");
          TextBoxFromXaml.SetBinding(TextBox.TextProperty, binding);
     }
}
public class MyClass2
{
     public string StringVar { get; set; }

     public MyClass2()
     {
          StringVar = "My String Here";
     }
}

public partial class Window1 : Window
{
	public MyClass2 MyClass2Object { get; set; }
	public Window1()
	{
		// use data context instead of source
		DataContext = this;

		InitializeComponent();

		MyClass2Object = new MyClass2();
		Binding binding = new Binding();
		binding.Path = new PropertyPath("MyClass2Object.StringVar");
		TextBoxFromXaml.SetBinding(TextBox.TextProperty, binding);
	}
}

public class MyClass2
{
	public string StringVar { get; set; }
	public MyClass2()
	{
		StringVar = "My String Here";
	}
}