How to drag from a ListBoxDragDropTarget to a exactly listbox(not a ListBoxDragDropTarget)?

My code is all here.But when I dragged the item in the left listboxDragDropTarge,it simply doesn't work.
<grid x:name="LayoutRoot" removed="White">
<toolkit:listboxdragdroptarget allowdrop="True">
<ListBox Name="lst" ItemsSource="{Binding}" Margin="36,23,0,132" HorizontalAlignment="Left" Width="131"
AllowDrop="True" >
<ListBox.ItemTemplate>
<datatemplate>
<stackpanel orientation="Horizontal">
<textblock text="{Binding Name}">
<textblock text="{Binding Age}">
<textblock text="{Binding Addr}">


</ListBox.ItemTemplate>
</ListBox>

<Button Click="Add_click" Content="Add input" Height="20" Margin="161,262,159,18"></Button>
<ListBox Height="145" HorizontalAlignment="Left" Margin="235,23,0,0" Name="ListBoxTarget" VerticalAlignment="Top"
Width="128" AllowDrop="True" Drop="List_Drop" ItemsSource="{Binding}">
<ListBox.ItemTemplate>
<datatemplate>
<stackpanel orientation="Horizontal">
<textblock text="{Binding Name}">
<textblock text="{Binding Age}">
<textblock text="{Binding Addr}">


</ListBox.ItemTemplate>
</ListBox>




namespace MyTrailListBox
{
public class Person
{
public string Name { get; set; }
public string Age { get; set; }
public string Addr { get; set; }
public Person(string name, string age, string addr)
{
Name = name;
Age = age;
Addr = addr;
}
}
}



namespace MyTrailListBox
{
public class Persons:ObservableCollection<Person>
{
public Persons()
{
Add(new Person("Aimy", "17", "Hubei"));
Add(new Person("John", "19", "Wuhan"));

}
}
}


namespace MyTrailListBox
{
public partial class MainPage : UserControl
{
public MainPage()
{
InitializeComponent();
this.DataContext = p;
ListBoxTarget.DataContext = p2;
}
public Persons p=new Persons();
public Persons p2 = new Persons();
private void Add_click(object sender, RoutedEventArgs e)
{
p.Add(new Person("Good", "20", "sdfa"));
p2.Add(new Person("Evening ", "20", " suohe"));

}
IEnumerable<Person> selectedItem;
private void List_Drop(object sender, DragEventArgs e)
{
ItemDragEventArgs itemDrag;
itemDrag= e.Data.GetData(e.Data.GetFormats()[0]) as ItemDragEventArgs;
SelectionCollection selectionCollection = itemDrag.Data as SelectionCollection;
if (selectionCollection != null)
{
selectedItem = selectionCollection.Select(selection => selection.Item).OfType<Person>();
}
var data = (ObservableCollection<Person>)selectedItem;
foreach (var item in data)
p2.Add(item);
e.Handled = true;
}
}
}