Using D&D ,how to delete from text box and sync the list box

Im having list box and there is option to D&D from list box to text box

Currently i don't know how to implement the scenario when the user is regret and want to delete the value from the text box.

There is two option of deleting the value i guess.

1. Mark the cursor on the end of text box value and delete it with the arrow (<-) character by character

2. mark all the value with the mouse and delete it by pressing on the delete button on the keyboard

I know that there is option to use the following event but this is very complicated I guess since if user use the first option to delete...

TextChanged="textbox_TextChanged"

(when the value is deleted the list view should be updated)

I'm Stuck :(,

I need your help please ...

if this is not the right forum ,please let me know.

Following is the code

UserControl x:Class="DD.Views.ModelView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             d:DesignHeight="300" d:DesignWidth="300"><Grid><StackPanelOrientation="Vertical"Visibility="Visible"><ListBox x:Name="LstUsers"Height="115"Width="150"ItemsSource="{Binding UsersCollectionView}"SelectionChanged="listbox_SelectionChanged"AllowDrop="True"PreviewDrop="ListBox_PreviewDrop"><ListBox.ItemTemplate><DataTemplate><TextBlockText="{Binding Name}"/></DataTemplate></ListBox.ItemTemplate></ListBox><TextBox x:Name="textbox1"  
                 AllowDrop="True" 
                 PreviewMouseDown="DropText_PreviewMouseDown"
                 PreviewDragEnter="DropText_PreviewDragEnter"
                 PreviewDrop="DropText_PreviewDrop"
                 AcceptsReturn="True"
                 TextWrapping="Wrap"
                 Height="50"
                 Width="120"/><TextBox x:Name="textbox2"AllowDrop="True"PreviewMouseDown="DropText_PreviewMouseDown"PreviewDragEnter="DropText_PreviewDragEnter"PreviewDrop="DropText_PreviewDrop"AcceptsReturn="True"TextWrapping="Wrap"Height="50"Width="120"/></StackPanel></Grid></UserControl>

View model

internalclassModelViewModel{privateObservableCollection<User>_UsersList;privateICollectionView usersCollectionView;publicICollectionViewUsersCollectionView{get{return usersCollectionView;}}publicObservableCollection<User>UserList{get{return_UsersList;}}publicModelViewModel(){_UsersList=newObservableCollection<User>();_UsersList.Add(newUser{Name="Person01"});_UsersList.Add(newUser{Name="Person02"});_UsersList.Add(newUser{Name="Person03"});
            usersCollectionView =CollectionViewSource.GetDefaultView(_UsersList);UsersCollectionView.SortDescriptions.Add(newSortDescription("Name",ListSortDirection.Ascending));}

The View

publicpartialclassModelView:UserControl{privateconststring DRAG_SOURCE ="DragSource";privatestaticModelViewModelModelViewInstance;publicMyUserControl(){InitializeComponent();ModelViewInstance=newModelViewModel();this.DataContext=ModelViewInstance;}privatevoidDropText_PreviewDrop(object sender,DragEventArgs e){var textbox =(TextBox)sender;if(!(textbox.Text.Length>0)){string name = e.Data.GetData(DataFormats.StringFormat).ToString();
                textbox.Text+= name;
                textbox.Focus();
                textbox.CaretIndex= textbox.Text.Length;
                e.Handled=true;ModelViewInstance.UserList.Remove(LstUsers.SelectedItemasUser);}else{
                e.Handled=true;}}privatevoidListBox_PreviewDrop(object sender,DragEventArgs e){object dragSource = e.Data.GetData(DRAG_SOURCE);if(dragSource !=null&& dragSource isTextBox){(dragSource asTextBox).Text=String.Empty;}if(!String.IsNullOrEmpty(e.Data.GetData(DataFormats.StringFormat).ToString())&& dragSource isTextBox){var newUser =newUser{Name= e.Data.GetData(DataFormats.StringFormat).ToString()};ModelViewInstance.UserList.Add(newUser);}else{
                e.Handled=true;}}privatevoidDropText_PreviewMouseDown(object sender,MouseButtonEventArgs e){var textBox =(TextBox)sender;if(textBox !=null){var dataObject =newDataObject((textBox).Text);
                dataObject.SetData("DragSource", sender);DragDrop.DoDragDrop(textBox, dataObject,DragDropEffects.Copy|DragDropEffects.Move);}}privatevoid listbox_SelectionChanged(object sender,SelectionChangedEventArgs e){if(sender isListBox){var listBox = sender asListBox;if(e.AddedItems.Count==1){if(listBox.SelectedItem!=null){var mySelectedItem = listBox.SelectedItemasUser;if(mySelectedItem !=null){DragDrop.DoDragDrop(listBox, mySelectedItem.Name,DragDropEffects.Copy|DragDropEffects.Move);}}}}}