how to split listbox items to some textbox

Question

Hi All.

My form has three TextBox. When user enter data to those TextBox and press Add button the data will display in ListBox like one item. For that I use code

TextList.Items.Add(CustomerNoTextBox.Text + VisitNoTextBox.Text + "-" + NoTextBox.Text)

For instance, user enter: TextBox1 - 123456 TextBox2- 7 and TextBox3 - 89.

By click Add button the ListBox will display 1234567-89.

Now I would like in case if will need to modify entered date user will select ListBoxItem and data of that item will display in each TextBox like was entered. If that possible how it to do? I will appreaciat for sample.

Thanks. 

Answer 1

Hi eugzl,

CustomerNoTextBox(6), VisitNoTextBox(1), NoTextBox(2) these fields have fixed size or user can enter any length of data.

Regards

Ashish

Answer 2

Hi Ashish. Thanks for replay.

All TextBox have fixed legth of data.

Thanks.

Answer 3

Hello Eugzl.

I got to playing with your described scenario and came up with the following.  My thinking was that if textBox1 and textBox2 did not have set lengths then you would need to keep track of each.  So I created a ListBoxItem with 3 Properties to keep track.

Here's the sample...

using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace CombiningText
{
	public partial class MainWindow : Window
	{
		public MainWindow()
		{
			this.InitializeComponent();
		}

		private void Button_Click(object sender, System.Windows.RoutedEventArgs e)
		{
			if (btn.Content.ToString() == "Add")
				addNew();
			else
			{
				foreach(myListBoxItem lb in myListBox.Items)
				{
					if (lb.InEdit)
						edit(lb);
				}
			}
		}
		
		private void editSelected(object sender, MouseButtonEventArgs e)
		{
			btn.Content = "Edit";
			myListBoxItem lbi = sender as myListBoxItem;
			lbi.InEdit = true;
			tb1.Text = lbi.String1;
			tb2.Text = lbi.String2;
			tb3.Text = lbi.String3;
		}
		
		private void edit(myListBoxItem lbi)
		{
			lbi.InEdit = false;
			lbi.String1 = tb1.Text;
			lbi.String2 = tb2.Text;
			lbi.String3 = tb3.Text;
			lbi.setContent();
			tb1.Text = tb2.Text = tb3.Text = "";
			btn.Content = "Add";
		}
		
		private void addNew()
		{
			myListBoxItem lbi = new myListBoxItem();
			lbi.String1 = tb1.Text;
			lbi.String2 = tb2.Text;
			lbi.String3 = tb3.Text;
			lbi.InEdit = false;
			lbi.MouseDoubleClick += editSelected;
			lbi.setContent();
			myListBox.Items.Add(lbi);
			tb1.Text = tb2.Text = tb3.Text = "";
		}
	}
	
	public class myListBoxItem : ListBoxItem
	{
		[Category("Item Settings")]
		public string String1 { get { return (string)GetValue(String1Property); } set { SetValue(String1Property, value); }}
		public static readonly DependencyProperty String1Property = DependencyProperty.Register("String1", typeof(string), typeof(myListBoxItem), null);
		
		[Category("Item Settings")]
		public string String2 { get { return (string)GetValue(String2Property); } set { SetValue(String2Property, value); }}
		public static readonly DependencyProperty String2Property = DependencyProperty.Register("String2", typeof(string), typeof(myListBoxItem), null);
		
		[Category("Item Settings")]
		public string String3 { get { return (string)GetValue(String3Property); } set { SetValue(String3Property, value); }}
		public static readonly DependencyProperty String3Property = DependencyProperty.Register("String3", typeof(string), typeof(myListBoxItem), null);
		
		[Category("Item Settings")]
		public bool InEdit { get { return (bool)GetValue(InEditProperty); } set { SetValue(InEditProperty, value); }}
		public static readonly DependencyProperty InEditProperty = DependencyProperty.Register("InEdit", typeof(bool), typeof(myListBoxItem), null);
		
		
		public void setContent()
		{
			string content = String1 + String2 + "-" + String3;
			this.Content = content;
		}
	}
}

And the xaml...

<Window
	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" 
	x:Class="CombiningText.MainWindow"
	x:Name="Window"
	Title="MainWindow"
	Width="640" Height="480">

	<Grid x:Name="LayoutRoot">
		<StackPanel HorizontalAlignment="Left" VerticalAlignment="Top" Margin="8,8,0,0">
			<TextBox x:Name="tb1" TextWrapping="Wrap" Text="TextBox" Margin="5" SelectionOpacity="5" Width="100"/>
			<TextBox x:Name="tb2" TextWrapping="Wrap" Text="TextBox" Margin="5" SelectionOpacity="5" Width="100"/>
			<TextBox x:Name="tb3" TextWrapping="Wrap" Text="TextBox" Margin="5" SelectionOpacity="5" Width="100"/>
		</StackPanel>
		<Button x:Name="btn" Content="Add" HorizontalAlignment="Left" VerticalAlignment="Top" Width="100" Margin="8,118,0,0" Click="Button_Click"/>
		<ListBox x:Name="myListBox" Margin="200,8,0,0" Height="200" VerticalAlignment="Top" HorizontalAlignment="Left" Width="150"/>
	</Grid>
</Window>

Double-Clicking an item added to the listBox will allow it to be edited.

Hope that gives you some ideas.

~Christine

Woops.  Forgive the intrusion.  I had this open and didn't see that agrawal was already addressing your question.

---

My Gallery

Answer 4

Hi Christine. Thanks for replay.

Your code is greate. In my code I have Delete button for in case user enter wrong or extra data. The code of Delete button:

    Private Sub DelButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
        TextList.Items.RemoveAt(TextList.Items.IndexOf(TextList.SelectedItem))
    End Sub

But if ListBoxItem is not selected I got error message: "removeIndex is less than zero or greater than or equal to Count. Parameter name: index."

How modify your code to add Delete button and avoid such problem?

Thanks.

Answer 5

Howdy Eugzl.

My first thought was "why not do it with a right-click?" but it's not my place to pretend to know your thinking and how you have your project set up.

So if you have a delete button, what if you had it hidden/collapsed until it could be used.  So you double click and can edit or delete the item and use the foreach loop to find and remove it if deleting.

  Something like this.  (Note because I am right stubborn when I get something in my head, I included the right-click to delete method as well.  :) )

using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace CombiningText
{
	public partial class MainWindow : Window
	{
		public MainWindow()
		{
			this.InitializeComponent();
		}

		private void Button_Click(object sender, System.Windows.RoutedEventArgs e)
		{
			if (btn.Content.ToString() == "Add")
				addNew();
			else
			{
				foreach(myListBoxItem lb in myListBox.Items)
				{
					if (lb.InEdit)
						edit(lb);
				}
			}
		}
		
		private void editSelected(object sender, MouseButtonEventArgs e)
		{
			btn.Content = "Edit";
			deleteBtn.Visibility = Visibility.Visible;
			myListBoxItem lbi = sender as myListBoxItem;
			lbi.InEdit = true;
			tb1.Text = lbi.String1;
			tb2.Text = lbi.String2;
			tb3.Text = lbi.String3;
		}
		
		private void edit(myListBoxItem lbi)
		{
			lbi.InEdit = false;
			lbi.String1 = tb1.Text;
			lbi.String2 = tb2.Text;
			lbi.String3 = tb3.Text;
			lbi.setContent();
			tb1.Text = tb2.Text = tb3.Text = "";
			btn.Content = "Add";
		}
		
		private void addNew()
		{
			myListBoxItem lbi = new myListBoxItem();
			lbi.String1 = tb1.Text;
			lbi.String2 = tb2.Text;
			lbi.String3 = tb3.Text;
			lbi.InEdit = false;
			lbi.MouseDoubleClick += editSelected;
            
            		//Right-Click Delete
            		lbi.PreviewMouseRightButtonDown += deleteByRightClick;
			
            		lbi.setContent();
			myListBox.Items.Add(lbi);
			tb1.Text = tb2.Text = tb3.Text = "";
		}

		private void DeleteItem(object sender, System.Windows.RoutedEventArgs e)
		{
            		myListBoxItem lbi = new myListBoxItem();
			foreach(myListBoxItem lb in myListBox.Items)
			{
				if (lb.InEdit)
				{
                    			lbi = lb;
				}
			}
            		if (lbi != null)
            		{
                		myListBox.Items.Remove(lbi);
                		tb1.Text = tb2.Text = tb3.Text = "";
                		btn.Content = "Add";
                		deleteBtn.Visibility = Visibility.Collapsed;
            		}
		}

        	private void deleteByRightClick(object sender, MouseButtonEventArgs e)
        	{
            		myListBoxItem lbi = sender as myListBoxItem;
            		var result = MessageBox.Show("Delete Selected Item?", "Delete Item", MessageBoxButton.YesNo);
            		if (result == MessageBoxResult.Yes)
            		{
                		myListBox.Items.Remove(lbi);
            		}
        	}
	}

And the simple deleteBtn xaml...

<Button x:Name="deleteBtn" Content="Delete" HorizontalAlignment="Left" VerticalAlignment="Top" Width="100" Margin="8,143.96,0,0" Click="DeleteItem" Visibility="Collapsed"/>

~Chritine

---

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Answer 6

Use the Tag property to hold the values seperated by pipe characters. I have three textboxes (tbOne, tbTwo, tbThree) a button and a listbox (lbLoad). On the button press I get the values and load the listbox with an item. If the user double clicks I extract the Tag information and load the textboxes. Since you have delete you will need to remove the listbox item for editing. Here is the code:

private List<TextBox> _tbs;
public List<TextBox> TextBoxes
{
    get
    {
        if (_tbs == null)
            _tbs = new List<TextBox> {tbOne, tbTwo, tbThree};

        return _tbs;
    }
}
private void btnAdd_Click( object sender, RoutedEventArgs e )
{
    var strings = TextBoxes.Select( tb => tb.Text );

    lbLoad.Items.Add(new ListBoxItem()
        {
            Content = string.Join( string.Empty, strings.ToArray() ),
            Tag = string.Join( "|", strings.ToArray() )
        }
        );

    // Clear the textboxes
    TextBoxes.ToList()
                .ForEach(tb => tb.Text = string.Empty);

}

private void lbLoad_MouseDoubleClick( object sender, MouseButtonEventArgs e )
{

    var item = lbLoad.SelectedItem as ListBoxItem;

    if (item != null)
    {
        if (item.Tag != null)
        {
            string data = (string)item.Tag;

            if (string.IsNullOrEmpty(data) == false)
            {
                var splitData = data.Split('|');
                TextBoxes.Select((tb, index) => new {tb, index})
                            .ToList()
                            .ForEach(tbItem => tbItem.tb.Text = splitData[tbItem.index]);
            }
        }
    }
}

---

William Wegerson (www.OmegaCoder.Com)

Answer 7

Hi All. Thanks for all replays.

I modified ADD procedure to fill ListBox and save data to DataSet CustomerEnterTableAdapter that is point to database SQL Server at the same time. The same I would like to do with EDIT procedure. If need to modify data I will modify data in TextBox and then display modified data in LIstBox and save it to the table by click Edit button.

    Public Sub New()
        ' This call is required by the Windows Form Designer.
        InitializeComponent()

        Me.cvCustomerEntry = CollectionViewSource.GetDefaultView(Me.CustomerDataSet.CustomerEntry)
        Me.DataContext = Me.cvCustomerEntry
    End Sub

    Private Sub addNew()
        Dim Errors As Boolean = False
        Dim lbi As New myListBoxItem()

        If Validation.GetHasError(Me.MedRecNoTextBox) Then
            Me.MedRecNoTextBox.Focus()
            Errors = True
            Beep()
        End If

        If Validation.GetHasError(Me.VisitNoTextBox) Then
            Me.VisitNoTextBox.Focus()
            Errors = True
            Beep()
        End If

        If Validation.GetHasError(Me.NoTextBox) Then
            Me.NoTextBox.Focus()
            Errors = True
            Beep()
        End If

        If Errors = True Then
            MsgBox("Please, fill in all reruired fields")
        Else
            lbi.String1 = CustomerNoTextBox.Text
            lbi.String2 = VisitNoTextBox.Text
            lbi.String3 = NoTextBox.Text
            lbi.InEdit = False
            AddHandler lbi.MouseDoubleClick, AddressOf editSelected
            lbi.setContent()
            myListBox.Items.Add(lbi)

            Me.CustomerEntryTableAdapter.Update(Me.CustomerDataSet.CustomerEntry)
        End If

        CustomerNoTextBox.Text = InlineAssignHelper(VisitNoTextBox.Text, InlineAssignHelper(NoTextBox.Text, ""))
        CustomerNoTextBox.Focus()
    End Sub

When I open form fill 3 TextBox and click Add button everything works fine. But when I try to add data to ListBox againe I got error message: Update requires a valid UpdateCommand when passed DataRow collection with modified rows.
My goal to add data to LIstBox so many time as need. I validate TextBox for numeric and length entered data. How to fix that problem?

Thanks.

Answer 8

Hi eugzl,

I think your WPF relative issue has been resolved, because " myListBox.Items.Add(lbi)" will work well, and the error message "Update requires a valid UpdateCommand when passed DataRow collection with modified rows." is more relative to Ado.net forum as I suggested before:

On the other hand, WPF and Winform are two different technology, I do not suggest you use WPF ListBox as winform's:

 lbi.String1 = CustomerNoTextBox.Text
            lbi.String2 = VisitNoTextBox.Text
            lbi.String3 = NoTextBox.Text
            lbi.InEdit = False
            AddHandler lbi.MouseDoubleClick, AddressOf editSelected
            lbi.setContent()
            myListBox.Items.Add(lbi)

I suggest you learn more about DataTemplate of ListBox:

http://msdn.microsoft.com/en-us/library/system.windows.datatemplate.aspx

Best regards,

---

Sheldon _Xiao[MSFT]
MSDN Community Support | Feedback to us
Microsoft
Please remember to mark the replies as answers if they help and unmark them if they provide no help.

Answer 9

Hi All.

I modified New procedure like

    Public Sub New()
        ' This call is required by the Windows Form Designer.
        InitializeComponent()
        Me.cvCustomeEntry = CollectionViewSource.GetDefaultView(Me.CustomerDataSet.CustomerEntry)
        myListBox.DataContext = Me.cvCustomeEntry
    End Sub

Previously I had Me.DataContext = Me.cvCustomeEntry. Now I can add data to ListBox as many time as need. But when I click Add button the CustomerEntry table receive only one empty row. How fix that problem?

Thanks.

Answer 10

I think you are missing Sheldon’s point, with WPF you are better off leveraging Data Binding. By binding Presentation of the data to data source all you have to do in the code behind is manipulate the data not the UI. Any time you add, remove Items to your data you add/remove it from the data source not the UI elements. Because the UI is bound to the data it will reflect the changes automatically. On the flip side if the properties of your items have changed via the User/UI the data source is automatically updated.

Below is an example you can see there is very little code behind to try it create a new WPF project and paste the below XAML over window1’s XAML and Code over window1’s code

XAML:

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525" >
    <Window.Resources>
        <Style x:Key="styEdit" TargetType="TextBox">
            <Setter Property="IsEnabled"
                    Value="{Binding ElementName=butEdit, Path=IsChecked}"/>
        </Style>
        <BooleanToVisibilityConverter x:Key="VisConv" />
    </Window.Resources>
    <Grid Name="grdLayout" ButtonBase.Click="Button_Click">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="120" />
            <ColumnDefinition Width="1*" />
        </Grid.ColumnDefinitions>
        <ListBox Name="lstVisits" 
                 ItemsSource="{Binding}" IsSynchronizedWithCurrentItem="True">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <TextBlock FontSize="14">
                            <Run Text="{Binding CustomerNo}"/>
                            <Run Text="-"/>
                            <Run FontSize="12" Text="{Binding Path=VisitNo}"/>
                            <Run Text="-"/>
                            <Run FontSize="10" Text="{Binding Path=No}"/>
                        </TextBlock>
                        <Ellipse Fill="#FF40D840" 
                                   Stroke="Black" 
                                   StrokeThickness="0.5"
                                   Margin="5,0"
                                   Width="7"
                                   Height="7" 
                                   Visibility="{Binding Path=FrequentVisitor, 
                                   Converter={StaticResource ResourceKey=VisConv}}" />
                    </StackPanel>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
        <Button Name="butZero" Content="Clear All" 
                HorizontalAlignment="Right" 
                VerticalAlignment="Top" 
                Grid.Column="1"
                Margin="10"/>
        <StackPanel Grid.Column="1"
                    VerticalAlignment="Center"
                    HorizontalAlignment="Center">
            <StackPanel Orientation="Horizontal"
                        HorizontalAlignment="Center">
                <TextBox Name="txtCustomerNo"
                         Text="{Binding Path=CurrentItem.CustomerNo}"
                         Style="{StaticResource styEdit}"/>
                <TextBlock Text="-" Margin="3,0"/>
                <TextBox Text="{Binding CurrentItem.VisitNo}"
                         Style="{StaticResource styEdit}"/>
                <TextBlock Text="-" Margin="3,0"/>
                <TextBox Text="{Binding CurrentItem.No}"
                         Style="{StaticResource styEdit}"/>
            </StackPanel>
            <StackPanel Orientation="Horizontal"
                        HorizontalAlignment="Center">
                <Button Name="butAdd" Content="Add"/>
                <Button Name="butDelete" Content="Delete"/>
                <ToggleButton Name="butEdit" Content="Edit"/>
            </StackPanel>
        </StackPanel>
    </Grid>
</Window>

VB Code:

Imports System.Collections.ObjectModel
Imports System.ComponentModel

Class MainWindow
    Private _CustomerVisits As ObservableCollection(Of CustomerVisit)
    Public ReadOnly Property CustomerVisits() As ObservableCollection(Of CustomerVisit)
        Get
            If _CustomerVisits Is Nothing Then
                _CustomerVisits = New ObservableCollection(Of CustomerVisit)

                AddHandler _CustomerVisits.CollectionChanged, AddressOf CustomerVisit_CollectionChanged
            End If

            Return _CustomerVisits
        End Get
    End Property

    Private Sub CustomerVisit_PropertyChanged(sender As Object, _
                                              e As ComponentModel.PropertyChangedEventArgs)
        'Code to update database with edits here
    End Sub

    Private Sub CustomerVisit_CollectionChanged(sender As Object, _
                                                e As Specialized.NotifyCollectionChangedEventArgs)
        'Code to add and delete from database here
    End Sub

    Private Sub Button_Click(sender As System.Object, e As System.Windows.RoutedEventArgs)
        If TypeOf e.OriginalSource Is Button Then
            Dim ClickedButton As Button = CType(e.OriginalSource, Button)
            Dim custVisit As CustomerVisit

            Select Case ClickedButton.Name
                Case butAdd.Name
                    custVisit = New CustomerVisit

                    'add items to bound collection
                    '       not from the listbox
                    CustomerVisits.Add(custVisit)

                    lstVisits.SelectedItem = custVisit
                    butEdit.IsChecked = True

                    txtCustomerNo.SelectAll()
                    txtCustomerNo.Focus()

                Case butDelete.Name

                    'remove items from bound collection
                    '   not from the listbox.
                    CustomerVisits.Remove(lstVisits.SelectedItem)

                Case butZero.Name
                    'clears all values
                    For Each custVisit In CustomerVisits
                        With custVisit
                            .CustomerNo = 0
                            .VisitNo = 0
                            .No = 0
                        End With
                    Next

            End Select
        End If

    End Sub

    Private Sub lstVisits_SelectionChanged(sender As Object, _
                                           e As System.Windows.Controls.SelectionChangedEventArgs) _
                                       Handles lstVisits.SelectionChanged


        butEdit.IsChecked = False
    End Sub

    'below code fills the CustomerVisits list with random data
    Private Sub MainWindow_Loaded(sender As Object, e As System.Windows.RoutedEventArgs) Handles Me.Loaded
        grdLayout.DataContext = CustomerVisits

        LoadCustomerVisits()
    End Sub

    Private Sub LoadCustomerVisits()
        Dim newVisit As CustomerVisit
        Dim mRand As New Random

        For i As Integer = 1 To 10
            newVisit = New CustomerVisit

            With newVisit
                .CustomerNo = mRand.Next(1000, 9999)
                .VisitNo = mRand.Next(100, 999)
                .No = mRand.Next(1, 10)
            End With

            AddHandler newVisit.PropertyChanged, AddressOf CustomerVisit_PropertyChanged

            CustomerVisits.Add(newVisit)
        Next
    End Sub
End Class

'Models the Customer Visit
Public Class CustomerVisit
    'must implement for databinding
    Implements INotifyPropertyChanged

    Public Event PropertyChanged(ByVal sender As Object, _
                                 ByVal e As System.ComponentModel.PropertyChangedEventArgs) _
                             Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged

    Protected Overridable Sub OnPropertyChanged(ByVal ChangedProperty As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(ChangedProperty))
    End Sub

    Private _CustomerNo As Integer
    Public Property CustomerNo() As Integer
        Get
            Return _CustomerNo
        End Get
        Set(ByVal value As Integer)
            _CustomerNo = value

            OnPropertyChanged("CustomerNo")
        End Set
    End Property

    Private _VisitNo As Integer
    Public Property VisitNo() As Integer
        Get
            Return _VisitNo
        End Get
        Set(ByVal value As Integer)
            _VisitNo = value

            OnPropertyChanged("VisitNo")
        End Set
    End Property

    Private _No As Integer
    Public Property No() As Integer
        Get
            Return _No
        End Get
        Set(ByVal value As Integer)
            _No = value

            OnPropertyChanged("No")
            OnPropertyChanged("FrequentVisitor")
        End Set
    End Property

    Public ReadOnly Property FrequentVisitor() As Boolean
        Get
            Return No > 6
        End Get
    End Property
End Class

Answer 11

Hi eugzl,

As I said before, if you use " myListBox.DataContext = Me.cvCustomeEntry", and then set ItemsSource={Binding}, your ListBox will generate by binding, you cannot use ListBox.Items.Add() to add your item any more, you have to do add/remove with datasource, WPF is different from winform, you should learn more about binding, and what is WPF UI, and what is Data source.

Best regards,

---

Sheldon _Xiao[MSFT]
MSDN Community Support | Feedback to us
Microsoft
Please remember to mark the replies as answers if they help and unmark them if they provide no help.

Answer 12

Hi eugzl,

I am marking your issue as "Answered", if you need further discusstion,  please let us know.

Best regards,

---

Sheldon _Xiao[MSFT]
MSDN Community Support | Feedback to us
Microsoft
Please remember to mark the replies as answers if they help and unmark them if they provide no help.

Answer 13

> with WPF you are better off leveraging Data Binding

I concur with Techno and an excellent point at that...for WPF is data binding in an asyc fashion. Any Silverlight developer will tell you that, the sooner a WPF developer grasps that async methodology of data binding; the easier his/her life will be.

Thanks Techno for taking the time to create that example. :-)

---

William Wegerson (www.OmegaCoder.Com)

Answer 14

Hey OmegaMan;

What does async binding mean?

---

JP Cowboy Coders Unite!

Answer 15

> async binding mean

My bad...It is a philosophy for me in which I think of as "Async Binding".

For one sets up binding to a binding target in WPF as shown above. The when and the how that data gets to the target is transparent for a WPF coder. But a coder doing Silverlight does/uses the same binding mechanisim, but has to be cognizant of the acquisition of data and has to use actual asynchronous calls to fill the target of the binding whereas the WPF doesn't necessarily need to depending on circumstance.

To Xaml code, the binding is the same whether the data is called asychronously or not and doesn't do the process on screen til the InotifyPropertyChanged event occurs; that event in my mind is a defacto asynchronous system which I think of as Async Binding.

If one designs systems where the timing of the binding is inconsequential, an async fashion, it leads to an easier way of coding; just as the difference between Winforms and the WPF way.

I should stop thinking out loud and stick to standard nomenclature. :-)

---

William Wegerson (www.OmegaCoder.Com)

Answer 16

Indeed you are correct that the INotifyEvent by virtue of being an event is Asynchronous in nature.  This is one of the tricks I use when I design models "Use an event to signal when data is ready"  Because a Viewmodel can know the model, there's no problem hooking up an event listener in the ViewModel to the Model's DataReadyEvent!  This is push based, but I've even tried RX with very good results as well.  

---

JP Cowboy Coders Unite!