Shape.MouseDown - событие

Статья
11/01/2012

Происходит, когда указатель мыши находится над формой и нажатии кнопки мыши.

Пространство имен: Microsoft.VisualBasic.PowerPacks
Сборка: Microsoft.VisualBasic.PowerPacks.Vs (в Microsoft.VisualBasic.PowerPacks.Vs.dll)

Синтаксис

'Декларация
<BrowsableAttribute(True)> _
Public Event MouseDown As MouseEventHandler

[BrowsableAttribute(true)]
public event MouseEventHandler MouseDown

[BrowsableAttribute(true)]
public:
 event MouseEventHandler^ MouseDown {
    void add (MouseEventHandler^ value);
    void remove (MouseEventHandler^ value);
}

[<BrowsableAttribute(true)>]
member MouseDown : IEvent<MouseEventHandler,
    MouseEventArgs>

JScript не поддерживает события.

Заметки

События мыши происходят в следующем порядке.

MouseEnter

MouseMove

MouseHover / MouseDown / MouseWheel

MouseUp

MouseLeave

Дополнительные сведения об обработке событий см. в разделе Прием событий.

Примеры

В следующем примере показано использование MouseDown" MouseMoveи MouseUp события для рисования линии на a RectangleShape элемент управления.В этом примере необходима a RectangleShape наблюдение за RectangleShape2 с именем в форме.

Private mousePath = New System.Drawing.Drawing2D.GraphicsPath()

Private Sub RectangleShape2_MouseDown(
    ByVal sender As Object, 
     ByVal e As System.Windows.Forms.MouseEventArgs
  ) Handles RectangleShape2.MouseDown

    Dim mouseDownLocation As New Point(e.X + RectangleShape2.Left, 
      e.Y + RectangleShape2.Top)
    ' Clear the previous line.
    mousePath.Dispose()
    mousePath = New System.Drawing.Drawing2D.GraphicsPath()
    RectangleShape2.Invalidate()
    ' Add a line to the graphics path.
    mousePath.AddLine(mouseDownLocation, mouseDownLocation)
End Sub

Private Sub RectangleShape2_MouseMove(
    ByVal sender As Object, 
    ByVal e As System.Windows.Forms.MouseEventArgs
  ) Handles RectangleShape2.MouseMove

    Dim mouseX As Integer = e.X + RectangleShape2.Left
    Dim mouseY As Integer = e.Y + RectangleShape2.Top
    ' Add a line to the graphics path.
    mousePath.AddLine(mouseX, mouseY, mouseX, mouseY)
End Sub

Private Sub RectangleShape2_MouseUp(
    ByVal sender As Object, 
    ByVal e As System.Windows.Forms.MouseEventArgs
  ) Handles RectangleShape2.MouseUp

    Dim mouseUpLocation = New System.Drawing.Point(e.X + 
      RectangleShape2.Left, e.Y + RectangleShape2.Top)
    ' Add a line to the graphics path.
    mousePath.Addline(mouseUpLocation, mouseUpLocation)
    ' Force the shape to redraw.
    RectangleShape2.Invalidate()
End Sub

Private Sub RectangleShape2_Paint(
    ByVal sender As Object, 
    ByVal e As System.Windows.Forms.PaintEventArgs
  ) Handles RectangleShape2.Paint

    ' Draw the line.
    e.Graphics.DrawPath(System.Drawing.Pens.DarkRed, mousePath)
End Sub

private System.Drawing.Drawing2D.GraphicsPath mousePath = 
    new System.Drawing.Drawing2D.GraphicsPath();

private void rectangleShape2_MouseDown(object sender, 
    System.Windows.Forms.MouseEventArgs e)
{
    Point mouseDownLocation = new Point(e.X + rectangleShape2.Left, 
        e.Y + rectangleShape2.Top);
    // Clear the previous line.
    mousePath.Dispose();
    mousePath = new System.Drawing.Drawing2D.GraphicsPath();
    rectangleShape2.Invalidate();
    // Add a line to the graphics path.
    mousePath.AddLine(mouseDownLocation, mouseDownLocation);
}

private void rectangleShape2_MouseMove(object sender, 
    System.Windows.Forms.MouseEventArgs e)
{
    int mouseX = e.X + rectangleShape2.Left;
    int mouseY = e.Y + rectangleShape2.Top;
    // Add a line to the graphics path.
    mousePath.AddLine(mouseX, mouseY, mouseX, mouseY);
}

private void rectangleShape2_MouseUp(object sender, 
    System.Windows.Forms.MouseEventArgs e)
{
    System.Drawing.Point mouseUpLocation = 
        new System.Drawing.Point(e.X + rectangleShape2.Left, 
            e.Y + rectangleShape2.Top);
    // Add a line to the graphics path.
    mousePath.AddLine(mouseUpLocation, mouseUpLocation);
    // Force the shape to redraw.
    rectangleShape2.Invalidate();
}

private void rectangleShape2_Paint(object sender, 
    System.Windows.Forms.PaintEventArgs e)
{
    // Draw the line.
    e.Graphics.DrawPath(System.Drawing.Pens.DarkRed, mousePath);
}

Безопасность платформы .NET Framework

Полное доверие для непосредственно вызывающего метода. Этот член не может быть использован частично доверенным кодом. Дополнительные сведения см. в разделе Использование библиотек из не вполне надежного кода.