INotifyPropertyChanged, interface (System.ComponentModel)

Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Data.Common
Imports System.Diagnostics
Imports System.Drawing
Imports System.Data.SqlClient
Imports System.Windows.Forms

' This form demonstrates using a BindingSource to bind
' a list to a DataGridView control. The list does not
' raise change notifications, however the DemoCustomer type 
' in the list does.

Public Class Form1
    Inherits System.Windows.Forms.Form
    ' This button causes the value of a list element to be changed.
    Private changeItemBtn As New Button()
    
    ' This is the DataGridView control that displays the contents 
    ' of the list.
    Private customersDataGridView As New DataGridView()
    
    ' This is the BindingSource used to bind the list to the 
    ' DataGridView control.
    Private customersBindingSource As New BindingSource()
    
    Public Sub New() 
        ' Set up the "Change Item" button.
        Me.changeItemBtn.Text = "Change Item"
        Me.changeItemBtn.Dock = DockStyle.Bottom
        AddHandler Me.changeItemBtn.Click, AddressOf changeItemBtn_Click
        Me.Controls.Add(Me.changeItemBtn)
        
        ' Set up the DataGridView.
        customersDataGridView.Dock = DockStyle.Top
        Me.Controls.Add(customersDataGridView)
        Me.Size = New Size(800, 200)
        AddHandler Me.Load, AddressOf Form1_Load
    
    End Sub 'New
    
    Private Sub Form1_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Me.Load

        ' Create and populate the list of DemoCustomer objects
        ' which will supply data to the DataGridView.
        Dim customerList As New List(Of DemoCustomer)

        customerList.Add(DemoCustomer.CreateNewCustomer())
        customerList.Add(DemoCustomer.CreateNewCustomer())
        customerList.Add(DemoCustomer.CreateNewCustomer())

        ' Bind the list to the BindingSource.
        Me.customersBindingSource.DataSource = customerList

        ' Attach the BindingSource to the DataGridView.
        Me.customersDataGridView.DataSource = Me.customersBindingSource

    End Sub 'Form1_Load
    
    ' This event handler changes the value of the CompanyName
    ' property for the first item in the list.
    Private Sub changeItemBtn_Click(ByVal sender As Object, ByVal e As EventArgs) 
        ' Get a reference to the list from the BindingSource.
        Dim customerList As List(Of DemoCustomer) = _
            CType(customersBindingSource.DataSource, List(Of DemoCustomer))
        
        ' Change the value of the CompanyName property for the 
        ' first item in the list.
        customerList(0).CompanyName = "Tailspin Toys"
    
    End Sub
     
    
    
    <STAThread()>  _
    Shared Sub Main() 
        Application.EnableVisualStyles()
        Application.Run(New Form1())
    
    End Sub
End Class

' This class implements a simple customer type 
' that implements the IPropertyChange interface.

Public Class DemoCustomer
    Implements INotifyPropertyChanged
    ' These fields hold the values for the public properties.
    Private idValue As Guid = Guid.NewGuid()
    Private customerName As String = String.Empty
    Private companyNameValue As String = String.Empty
    Private phoneNumberValue As String = String.Empty
    
    Public Event PropertyChanged As PropertyChangedEventHandler _
        Implements INotifyPropertyChanged.PropertyChanged
    
    
    Private Sub NotifyPropertyChanged(ByVal info As String) 
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(info))
    End Sub

    ' The constructor is private to enforce the factory pattern.
    Private Sub New() 
        customerName = "no data"
        companyNameValue = "no data"
        phoneNumberValue = "no data"
    
    End Sub
    
    
    ' This is the public factory method.
    Public Shared Function CreateNewCustomer() As DemoCustomer 
        Return New DemoCustomer()
    
    End Function
    
    ' This property represents an ID, suitable
    ' for use as a primary key in a database.
    Public ReadOnly Property ID() As Guid
        Get
            Return Me.idValue
        End Get
    End Property
    
    
    Public Property CompanyName() As String 
        Get
            Return Me.companyNameValue
        End Get
        
        Set(ByVal value As String)
            If Not (value = companyNameValue) Then
                Me.companyNameValue = value
                NotifyPropertyChanged("CompanyName")
            End If
        End Set
    End Property
    
    
    Public Property PhoneNumber() As String 
        Get
            Return Me.phoneNumberValue
        End Get
        
        Set(ByVal value As String)
            If Not (value = phoneNumberValue) Then
                Me.phoneNumberValue = value
                NotifyPropertyChanged("PhoneNumber")
            End If

        End Set
    End Property
End Class

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.Common;
using System.Diagnostics;
using System.Drawing;
using System.Data.SqlClient;
using System.Windows.Forms;

// This form demonstrates using a BindingSource to bind
// a list to a DataGridView control. The list does not
// raise change notifications, however the DemoCustomer type 
// in the list does.
public class Form1 : System.Windows.Forms.Form
{
	// This button causes the value of a list element to be changed.
	private Button changeItemBtn = new Button();

	// This is the DataGridView control that displays the contents 
	// of the list.
	private DataGridView customersDataGridView = new DataGridView();

	// This is the BindingSource used to bind the list to the 
	// DataGridView control.
	private BindingSource customersBindingSource = new BindingSource();

	public Form1()
	{
		// Set up the "Change Item" button.
		this.changeItemBtn.Text = "Change Item";
		this.changeItemBtn.Dock = DockStyle.Bottom;
		this.changeItemBtn.Click +=
			new EventHandler(changeItemBtn_Click);
		this.Controls.Add(this.changeItemBtn);

		// Set up the DataGridView.
		customersDataGridView.Dock = DockStyle.Top;
		this.Controls.Add(customersDataGridView);
		this.Size = new Size(800, 200);
		this.Load += new EventHandler(Form1_Load);
	}

	private void Form1_Load(System.Object sender, System.EventArgs e)
	{
		// Create and populate the list of DemoCustomer objects
		// which will supply data to the DataGridView.
		List<DemoCustomer> customerList = new List<DemoCustomer>();
		customerList.Add(DemoCustomer.CreateNewCustomer());
		customerList.Add(DemoCustomer.CreateNewCustomer());
		customerList.Add(DemoCustomer.CreateNewCustomer());

		// Bind the list to the BindingSource.
		this.customersBindingSource.DataSource = customerList;

		// Attach the BindingSource to the DataGridView.
		this.customersDataGridView.DataSource =
			this.customersBindingSource;
	}

	// This event handler changes the value of the CompanyName
	// property for the first item in the list.
	void changeItemBtn_Click(object sender, EventArgs e)
	{
		// Get a reference to the list from the BindingSource.
		List<DemoCustomer> customerList =
			this.customersBindingSource.DataSource as List<DemoCustomer>;

		// Change the value of the CompanyName property for the 
		// first item in the list.
		customerList[0].CompanyName = "Tailspin Toys";

	}

	

	[STAThread]
	static void Main()
	{
		Application.EnableVisualStyles();
		Application.Run(new Form1());
	}
}

// This class implements a simple customer type 
// that implements the IPropertyChange interface.
public class DemoCustomer : INotifyPropertyChanged
{
	// These fields hold the values for the public properties.
	private Guid idValue = Guid.NewGuid();
	private string customerName = String.Empty;
	private string companyNameValue = String.Empty;
	private string phoneNumberValue = String.Empty;

	public event PropertyChangedEventHandler PropertyChanged;
	
	private void NotifyPropertyChanged(String info)
	{
		if (PropertyChanged != null)
		{
			PropertyChanged(this, new PropertyChangedEventArgs(info));
		}
	}

	// The constructor is private to enforce the factory pattern.
	private DemoCustomer()
	{
		customerName = "no data";
		companyNameValue = "no data";
		phoneNumberValue = "no data";
	}

	// This is the public factory method.
	public static DemoCustomer CreateNewCustomer()
	{
		return new DemoCustomer();
	}

	// This property represents an ID, suitable
	// for use as a primary key in a database.
	public Guid ID
	{
		get
		{
			return this.idValue;
		}
	}

	public string CompanyName
	{
		get
		{
			return this.companyNameValue;
		}

		set
		{
            if (value != this.companyNameValue)
            {
                this.companyNameValue = value;
                NotifyPropertyChanged("CompanyName");
            }
		}
	}

	public string PhoneNumber
	{
		get
		{
			return this.phoneNumberValue;
		}

		set
		{
            if (value != this.companyNameValue)
            {
                this.phoneNumberValue = value;
                NotifyPropertyChanged("PhoneNumber");
            }
		}
	}
}