Datepicker - 仅限年份？(Datepicker - year only?)

 RepositoryItemTextEdit类用于保存TextEdit类就地实例的属性。 技术上TextEdit类是保存TextBoxMaskBox类的实例的TextBoxMaskBox 。 TextBoxMaskBox类是从System.Windows.Forms.TextBox类继承的。 
 因此，您可以在自己的TextBoxMaskBox后代中创建自己的RepositoryItemTextEdit ， TextEdit和TextBoxMaskBox后代并覆盖WndProc方法。 
 这里是一个例子： 
 
[UserRepositoryItem("RegisterPasteHandlerEdit")]
public class RepositoryItemPasteHandlerEdit : RepositoryItemTextEdit
{
    static RepositoryItemPasteHandlerEdit()
    {
        RegisterPasteHandlerEdit();
    }

    static private readonly object EventPaste;

    public const string CustomEditName = "PasteHandlerEdit";

    public RepositoryItemPasteHandlerEdit() { }

    public override string EditorTypeName => CustomEditName;

    public static void RegisterPasteHandlerEdit()
    {
        Image img = null;
        EditorRegistrationInfo.Default.Editors.Add(new EditorClassInfo(CustomEditName, typeof(PasteHandlerEdit), typeof(RepositoryItemPasteHandlerEdit), typeof(TextEditViewInfo), new TextEditPainter(), true, img));
    }

    public override void Assign(RepositoryItem item)
    {
        BeginUpdate();
        try
        {
            base.Assign(item);
            var source = item as RepositoryItemPasteHandlerEdit;
            if (source == null) return;

            Events.AddHandler(EventPaste, source.Events[EventPaste]);
        }
        finally
        {
            EndUpdate();
        }
    }

    public event PasteEventHandler OnPaste
    {
        add
        {
            Events.AddHandler(EventPaste, value);
        }
        remove
        {
            Events.RemoveHandler(EventPaste, value);
        }
    }

    protected internal void RaiseOnPaste(PasteEventArgs e)
    {
        if (IsLockEvents)
            return;

        var handler = (PasteEventHandler)Events[EventPaste];
        handler?.Invoke(GetEventSender(), e);
    }
}

[ToolboxItem(true)]
public class PasteHandlerEdit : TextEdit
{
    static PasteHandlerEdit()
    {
        RepositoryItemPasteHandlerEdit.RegisterPasteHandlerEdit();
    }

    public PasteHandlerEdit() { }

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public new RepositoryItemPasteHandlerEdit Properties => base.Properties as RepositoryItemPasteHandlerEdit;

    public override string EditorTypeName => RepositoryItemPasteHandlerEdit.CustomEditName;

    protected override TextBoxMaskBox CreateMaskBoxInstance() => new PasteHandlerMaskBox(this);

    protected override void CreateMaskBox()
    {
        base.CreateMaskBox();

        var pasteHandlerMaskBox = MaskBox as PasteHandlerMaskBox;
        pasteHandlerMaskBox.OnPaste += PasteHandlerMaskBox_OnPaste;
    }

    private void PasteHandlerMaskBox_OnPaste(object sender, PasteEventArgs e) => Properties.RaiseOnPaste(e);
}

public class PasteHandlerMaskBox : TextBoxMaskBox
{
    private const int WM_PASTE = 0x0302;

    public PasteHandlerMaskBox(TextEdit ownerEdit) : base(ownerEdit) { }

    public event PasteEventHandler OnPaste;

    protected override void WndProc(ref Message msg)
    {
        if (msg.Msg == WM_PASTE)
        {
            var e = new PasteEventArgs();

            OnPaste?.Invoke(this, e);

            if (e.Cancel)
                return;
        }

        base.WndProc(ref msg);
    }
}

public class PasteEventArgs : CancelEventArgs
{
    public PasteEventArgs() { }
    public PasteEventArgs(bool cancel) : base(cancel) { }

    public string Text => Clipboard.GetText();
}

public delegate void PasteEventHandler(object sender, PasteEventArgs e);
 
 在这个例子中， OnPaste事件被添加到RepositoryItemPasteHandlerEdit类中。 你可以使用这个： 
 
private void repositoryItemPasteHandlerEdit1_OnPaste(object sender, PasteEventArgs e)
{
    MessageBox.Show(e.Text);

    if (...) // Perform some checks.
        e.Cancel = true;
}

RepositoryItemTextEdit class is used to hold the properties for in-place instance of TextEdit class. Technically TextEdit class is box which holds the instance of TextBoxMaskBox class. TextBoxMaskBox class is inherited from System.Windows.Forms.TextBox class.
 So, you can create your own RepositoryItemTextEdit, TextEdit and TextBoxMaskBox descendants and override WndProc method in your own TextBoxMaskBox descendant.
 Here is example:
 
[UserRepositoryItem("RegisterPasteHandlerEdit")]
public class RepositoryItemPasteHandlerEdit : RepositoryItemTextEdit
{
    static RepositoryItemPasteHandlerEdit()
    {
        RegisterPasteHandlerEdit();
    }

    static private readonly object EventPaste;

    public const string CustomEditName = "PasteHandlerEdit";

    public RepositoryItemPasteHandlerEdit() { }

    public override string EditorTypeName => CustomEditName;

    public static void RegisterPasteHandlerEdit()
    {
        Image img = null;
        EditorRegistrationInfo.Default.Editors.Add(new EditorClassInfo(CustomEditName, typeof(PasteHandlerEdit), typeof(RepositoryItemPasteHandlerEdit), typeof(TextEditViewInfo), new TextEditPainter(), true, img));
    }

    public override void Assign(RepositoryItem item)
    {
        BeginUpdate();
        try
        {
            base.Assign(item);
            var source = item as RepositoryItemPasteHandlerEdit;
            if (source == null) return;

            Events.AddHandler(EventPaste, source.Events[EventPaste]);
        }
        finally
        {
            EndUpdate();
        }
    }

    public event PasteEventHandler OnPaste
    {
        add
        {
            Events.AddHandler(EventPaste, value);
        }
        remove
        {
            Events.RemoveHandler(EventPaste, value);
        }
    }

    protected internal void RaiseOnPaste(PasteEventArgs e)
    {
        if (IsLockEvents)
            return;

        var handler = (PasteEventHandler)Events[EventPaste];
        handler?.Invoke(GetEventSender(), e);
    }
}

[ToolboxItem(true)]
public class PasteHandlerEdit : TextEdit
{
    static PasteHandlerEdit()
    {
        RepositoryItemPasteHandlerEdit.RegisterPasteHandlerEdit();
    }

    public PasteHandlerEdit() { }

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public new RepositoryItemPasteHandlerEdit Properties => base.Properties as RepositoryItemPasteHandlerEdit;

    public override string EditorTypeName => RepositoryItemPasteHandlerEdit.CustomEditName;

    protected override TextBoxMaskBox CreateMaskBoxInstance() => new PasteHandlerMaskBox(this);

    protected override void CreateMaskBox()
    {
        base.CreateMaskBox();

        var pasteHandlerMaskBox = MaskBox as PasteHandlerMaskBox;
        pasteHandlerMaskBox.OnPaste += PasteHandlerMaskBox_OnPaste;
    }

    private void PasteHandlerMaskBox_OnPaste(object sender, PasteEventArgs e) => Properties.RaiseOnPaste(e);
}

public class PasteHandlerMaskBox : TextBoxMaskBox
{
    private const int WM_PASTE = 0x0302;

    public PasteHandlerMaskBox(TextEdit ownerEdit) : base(ownerEdit) { }

    public event PasteEventHandler OnPaste;

    protected override void WndProc(ref Message msg)
    {
        if (msg.Msg == WM_PASTE)
        {
            var e = new PasteEventArgs();

            OnPaste?.Invoke(this, e);

            if (e.Cancel)
                return;
        }

        base.WndProc(ref msg);
    }
}

public class PasteEventArgs : CancelEventArgs
{
    public PasteEventArgs() { }
    public PasteEventArgs(bool cancel) : base(cancel) { }

    public string Text => Clipboard.GetText();
}

public delegate void PasteEventHandler(object sender, PasteEventArgs e);
 
In this example the OnPaste event is added to RepositoryItemPasteHandlerEdit class. You can use this:
 
private void repositoryItemPasteHandlerEdit1_OnPaste(object sender, PasteEventArgs e)
{
    MessageBox.Show(e.Text);

    if (...) // Perform some checks.
        e.Cancel = true;
}