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copied!<p>Here's an example that binds an object and some ancestors to the UI; the use of C# 3.0 here is purely for brevity - everything would work with C# 2.0 too.</p> <p>Most of the code here is setting up the form, and/or dealing with property-change notifications - importantly, there isn't any code devoted to updating the UI from the object model, or the object model from the UI.</p> <p>Note also the IDE can do a lot of the data-binding code for you, simply by dropping a BindingSource onto the form and setting the DataSource to a type via the dialog in the property grid.</p> <p>Note that it isn't essential to provide property change notifications (the PropertyChanged stuff) - however, most 2-way UI binding will work considerably better if you do implement this. Not that PostSharp has some interesting ways of doing this with minimal code.</p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.IO; using System.Windows.Forms; using System.Xml.Serialization; static class Program { // formatted for vertical space [STAThread] static void Main() { Application.EnableVisualStyles(); Button load, save, newCust; BindingSource source = new BindingSource { DataSource = typeof(Customer) }; XmlSerializer serializer = new XmlSerializer(typeof(Customer)); using (Form form = new Form { DataBindings = {{"Text", source, "Name"}}, // show customer name as form title Controls = { new DataGridView { Dock = DockStyle.Fill, // grid of orders DataSource = source, DataMember = "Orders"}, new TextBox { Dock = DockStyle.Top, ReadOnly = true, // readonly order ref DataBindings = {{"Text", source, "Orders.OrderRef"}}}, new TextBox { Dock = DockStyle.Top, // editable customer name DataBindings = {{"Text", source, "Name"}}}, (save = new Button { Dock = DockStyle.Bottom, Text = "save" }), (load = new Button{ Dock = DockStyle.Bottom, Text = "load"}), (newCust = new Button{ Dock = DockStyle.Bottom, Text = "new"}), } }) { const string PATH = "customer.xml"; form.Load += delegate { newCust.PerformClick(); // create new cust when loading form load.Enabled = File.Exists(PATH); }; save.Click += delegate { using (var stream = File.Create(PATH)) { serializer.Serialize(stream, source.DataSource); } load.Enabled = true; }; load.Click += delegate { using (var stream = File.OpenRead(PATH)) { source.DataSource = serializer.Deserialize(stream); } }; newCust.Click += delegate { source.DataSource = new Customer(); }; Application.Run(form); } } } [Serializable] public sealed class Customer : NotifyBase { private int customerId; [DisplayName("Customer Number")] public int CustomerId { get { return customerId; } set { SetField(ref customerId, value, "CustomerId"); } } private string name; public string Name { get { return name; } set { SetField(ref name, value, "Name"); } } public List<Order> Orders { get; set; } // XmlSerializer demands setter public Customer() { Orders = new List<Order>(); } } [Serializable] public sealed class Order : NotifyBase { private int orderId; [DisplayName("Order Number")] public int OrderId { get { return orderId; } set { SetField(ref orderId, value, "OrderId"); } } private string orderRef; [DisplayName("Reference")] public string OrderRef { get { return orderRef; } set { SetField(ref orderRef, value, "OrderRef"); } } private decimal orderValue, carriageValue; [DisplayName("Order Value")] public decimal OrderValue { get { return orderValue; } set { if (SetField(ref orderValue, value, "OrderValue")) { OnPropertyChanged("TotalValue"); } } } [DisplayName("Carriage Value")] public decimal CarriageValue { get { return carriageValue; } set { if (SetField(ref carriageValue, value, "CarriageValue")) { OnPropertyChanged("TotalValue"); } } } [DisplayName("Total Value")] public decimal TotalValue { get { return OrderValue + CarriageValue; } } } [Serializable] public class NotifyBase { // purely for convenience [field: NonSerialized] public event PropertyChangedEventHandler PropertyChanged; protected bool SetField<T>(ref T field, T value, string propertyName) { if (!EqualityComparer<T>.Default.Equals(field, value)) { field = value; OnPropertyChanged(propertyName); return true; } return false; } protected virtual void OnPropertyChanged(string propertyName) { PropertyChangedEventHandler handler = PropertyChanged; if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName)); } } </code></pre>

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