PaintEventArgs PaintEventArgs PaintEventArgs PaintEventArgs Class

Definizione

Fornisce dati per l'evento Paint.Provides data for the Paint event.

public ref class PaintEventArgs : EventArgs, IDisposable
public class PaintEventArgs : EventArgs, IDisposable
type PaintEventArgs = class
    inherit EventArgs
    interface IDisposable
Public Class PaintEventArgs
Inherits EventArgs
Implements IDisposable
Ereditarietà
PaintEventArgsPaintEventArgsPaintEventArgsPaintEventArgs
Derivato
Implementazioni

Esempi

Nell'esempio seguente viene illustrato come Paint gestire l'evento e PaintEventArgs come utilizzare la classe per creare rettangoli nel form.The following example demonstrates handling the Paint event and using the PaintEventArgs class to draw rectangles on the form. Gli MouseDown eventi MouseUp e vengono gestiti per determinare le dimensioni del rettangolo.The MouseDown and MouseUp events are handled to determine the size of the rectangle. Nell'esempio viene inoltre illustrato Invalidate il metodo per invalidare l'area del rettangolo, causando il ridisegnato.The example also demonstrates the Invalidate method to invalidate the area of the rectangle, causing it to be redrawn.

private:
   Rectangle RcDraw;
   void Form1_MouseDown( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
   {
      // Determine the initial rectangle coordinates...
      RcDraw.X = e->X;
      RcDraw.Y = e->Y;
   }

   void Form1_MouseUp( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
   {
      // Determine the width and height of the rectangle...
      if ( e->X < RcDraw.X )
      {
         RcDraw.Width = RcDraw.X - e->X;
         RcDraw.X = e->X;
      }
      else
      {
         RcDraw.Width = e->X - RcDraw.X;
      }

      if ( e->Y < RcDraw.Y )
      {
         RcDraw.Height = RcDraw.Y - e->Y;
         RcDraw.Y = e->Y;
      }
      else
      {
         RcDraw.Height = e->Y - RcDraw.Y;
      }

      // Force a repaint of the region occupied by the rectangle...
      this->Invalidate( RcDraw );
   }

   void Form1_Paint( Object^ /*sender*/, System::Windows::Forms::PaintEventArgs^ e )
   {
      // Draw the rectangle...
      float PenWidth = 5;
      e->Graphics->DrawRectangle( gcnew Pen( Color::Blue,PenWidth ), RcDraw );
   }

private Rectangle RcDraw;
private float PenWidth = 5;

private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{

	// Determine the initial rectangle coordinates...

	RcDraw.X = e.X;
	RcDraw.Y = e.Y;

}

private void Form1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
{

	// Determine the width and height of the rectangle...

	if(e.X < RcDraw.X)
	{
		RcDraw.Width = RcDraw.X - e.X;
		RcDraw.X = e.X;
	}
	else
	{
		RcDraw.Width = e.X - RcDraw.X;
	}

	if(e.Y < RcDraw.Y)
	{
		RcDraw.Height = RcDraw.Y - e.Y;
		RcDraw.Y = e.Y;
	}
	else
	{
		RcDraw.Height = e.Y - RcDraw.Y;
	}

	// Force a repaint of the region occupied by the rectangle...

	this.Invalidate(RcDraw);

}

private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
{

	// Draw the rectangle...

	e.Graphics.DrawRectangle(new Pen(Color.Blue, PenWidth), RcDraw);
	
}

Dim RcDraw As Rectangle
Dim PenWidth As Integer = 5


Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown

    ' Determine the initial rectangle coordinates...

    RcDraw.X = e.X
    RcDraw.Y = e.Y

End Sub

Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseUp

    ' Determine the width and height of the rectangle...

    If e.X < RcDraw.X Then
        RcDraw.Width = RcDraw.X - e.X
        RcDraw.X = e.X
    Else
        RcDraw.Width = e.X - RcDraw.X
    End If

    If e.Y < RcDraw.Y Then
        RcDraw.Height = RcDraw.Y - e.Y
        RcDraw.Y = e.Y
    Else
        RcDraw.Height = e.Y - RcDraw.Y
    End If

    ' Force a repaint of the region occupied by the rectangle...

    Me.Invalidate(RcDraw)

End Sub

Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint

    ' Draw the rectangle...

    e.Graphics.DrawRectangle(New Pen(Color.Blue, PenWidth), RcDraw)

End Sub


   // This example creates a PictureBox control on the form and draws to it.
   // This example assumes that the Form_Load event handler method is
   // connected to the Load event of the form.
private:
   PictureBox^ pictureBox1;
   void Form1_Load( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      pictureBox1 = gcnew PictureBox;

      // Dock the PictureBox to the form and set its background to white.
      pictureBox1->Dock = DockStyle::Fill;
      pictureBox1->BackColor = Color::White;

      // Connect the Paint event of the PictureBox to the event handler method.
      pictureBox1->Paint += gcnew System::Windows::Forms::PaintEventHandler( this, &Form1::pictureBox1_Paint );

      // Add the PictureBox control to the Form.
      this->Controls->Add( pictureBox1 );
   }

   void pictureBox1_Paint( Object^ /*sender*/, System::Windows::Forms::PaintEventArgs^ e )
   {
      // Create a local version of the graphics object for the PictureBox.
      Graphics^ g = e->Graphics;

      // Draw a string on the PictureBox.
      g->DrawString( "This is a diagonal line drawn on the control",
         gcnew System::Drawing::Font( "Arial",10 ), System::Drawing::Brushes::Blue, Point(30,30) );

      // Draw a line in the PictureBox.
      g->DrawLine( System::Drawing::Pens::Red, pictureBox1->Left, pictureBox1->Top,
         pictureBox1->Right, pictureBox1->Bottom );
   }
// This example creates a PictureBox control on the form and draws to it.
// This example assumes that the Form_Load event handler method is
// connected to the Load event of the form.

private PictureBox pictureBox1 = new PictureBox();
// Cache font instead of recreating font objects each time we paint.
private Font fnt = new Font("Arial",10);
private void Form1_Load(object sender, System.EventArgs e)
{
    // Dock the PictureBox to the form and set its background to white.
    pictureBox1.Dock = DockStyle.Fill;
    pictureBox1.BackColor = Color.White;
    // Connect the Paint event of the PictureBox to the event handler method.
    pictureBox1.Paint += new System.Windows.Forms.PaintEventHandler(this.pictureBox1_Paint);

    // Add the PictureBox control to the Form.
    this.Controls.Add(pictureBox1);
}

private void pictureBox1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
{
    // Create a local version of the graphics object for the PictureBox.
    Graphics g = e.Graphics;

    // Draw a string on the PictureBox.
    g.DrawString("This is a diagonal line drawn on the control",
        fnt, System.Drawing.Brushes.Blue, new Point(30,30));
    // Draw a line in the PictureBox.
    g.DrawLine(System.Drawing.Pens.Red, pictureBox1.Left, pictureBox1.Top,
        pictureBox1.Right, pictureBox1.Bottom);
}
' This example creates a PictureBox control on the form and draws to it. 
' This example assumes that the Form_Load event handler method is connected 
' to the Load event of the form.
Private pictureBox1 As New PictureBox()
Private fnt as New Font("Arial", 10)

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
    ' Dock the PictureBox to the form and set its background to white.
    pictureBox1.Dock = DockStyle.Fill
    pictureBox1.BackColor = Color.White
    ' Connect the Paint event of the PictureBox to the event handler method.
    AddHandler pictureBox1.Paint, AddressOf Me.pictureBox1_Paint

    ' Add the PictureBox control to the Form.
    Me.Controls.Add(pictureBox1)
End Sub


Private Sub pictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs)
    ' Create a local version of the graphics object for the PictureBox.
    Dim g As Graphics = e.Graphics

    ' Draw a string on the PictureBox.
    g.DrawString("This is a diagonal line drawn on the control", _
        fnt, Brushes.Red, New PointF(30.0F, 30.0F))
    ' Draw a line in the PictureBox.
    g.DrawLine(System.Drawing.Pens.Red, pictureBox1.Left, _ 
        pictureBox1.Top, pictureBox1.Right, pictureBox1.Bottom)
End Sub

Commenti

L' Paint evento si verifica quando un controllo viene ridisegnato.The Paint event occurs when a control is redrawn. Un PaintEventArgs oggetto specifica Graphics l'oggetto da utilizzare per disegnare il controllo ClipRectangle e l'oggetto in cui disegnare.A PaintEventArgs specifies the Graphics to use to paint the control and the ClipRectangle in which to paint.

Per informazioni sul modello di eventi, vedere gestione e generazione di eventi.For information about the event model, see Handling and Raising Events.

Costruttori

PaintEventArgs(Graphics, Rectangle) PaintEventArgs(Graphics, Rectangle) PaintEventArgs(Graphics, Rectangle) PaintEventArgs(Graphics, Rectangle)

Inizializza una nuova istanza della classe PaintEventArgs con le immagini e il rettangolo di ridimensionamento specificati.Initializes a new instance of the PaintEventArgs class with the specified graphics and clipping rectangle.

Proprietà

ClipRectangle ClipRectangle ClipRectangle ClipRectangle

Ottiene il rettangolo in cui disegnare.Gets the rectangle in which to paint.

Graphics Graphics Graphics Graphics

Ottiene il grafico usato per disegnare.Gets the graphics used to paint.

Metodi

Dispose() Dispose() Dispose() Dispose()

Rilascia tutte le risorse usate da PaintEventArgs.Releases all resources used by the PaintEventArgs.

Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

Rilascia le risorse non gestite usate da PaintEventArgs e, facoltativamente, le risorse gestite.Releases the unmanaged resources used by the PaintEventArgs and optionally releases the managed resources.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Determina se l'oggetto specificato è uguale all'oggetto corrente.Determines whether the specified object is equal to the current object.

(Inherited from Object)
Finalize() Finalize() Finalize() Finalize()

Consente a un oggetto di effettuare un tentativo di liberare risorse ed eseguire altre operazioni di pulizia prima che venga recuperato da Garbage Collection.Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Funge da funzione hash predefinita.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Ottiene l'oggetto Type dell'istanza corrente.Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Crea una copia superficiale dell'oggetto Object corrente.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Restituisce una stringa che rappresenta l'oggetto corrente.Returns a string that represents the current object.

(Inherited from Object)

Si applica a

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