Control.MouseWheel Evento

Definición

Se produce cuando la rueda del mouse se mueve mientras el control tiene el foco.Occurs when the mouse wheel moves while the control has focus.

public:
 event System::Windows::Forms::MouseEventHandler ^ MouseWheel;
[System.ComponentModel.Browsable(false)]
public event System.Windows.Forms.MouseEventHandler MouseWheel;
member this.MouseWheel : System.Windows.Forms.MouseEventHandler 
Public Custom Event MouseWheel As MouseEventHandler 
Atributos

Ejemplos

En el ejemplo de código siguiente se muestra cómo usar diferentes eventos del mouse para dibujar la ruta de acceso del mouse en un Panel.The following code example demonstrates using different mouse events to draw the path of the mouse on a Panel. Se agrega un segmento de línea al GraphicsPath para cada evento MouseMove y MouseDown que se produzca.A line segment is added to the GraphicsPath for each MouseMove and MouseDown events that occur. Para actualizar los gráficos, se llama al método Invalidate para la Panel en cada MouseDown y MouseUp evento.To update the graphics, the Invalidate method is called for the Panel on each MouseDown and MouseUp event. Además, la ruta de acceso del gráfico se desplaza hacia arriba o hacia abajo cuando se produce el evento MouseWheel.In addition, the graphic path is scrolled up or down when the MouseWheel event occurs. Los eventos de mouse adicionales, como MouseHover, también se identifican en la pantalla.Additional mouse events, like MouseHover, are identified on screen as well. También se muestra en la pantalla información adicional sobre el mouse desde la clase SystemInformation.Also displayed on the screen is additional information about the mouse from the SystemInformation class.

#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;

namespace MouseEvent
{
   public ref class Form1: public System::Windows::Forms::Form
   {
   private:
      System::Windows::Forms::Panel^ panel1;
      System::Windows::Forms::Label ^ label1;
      System::Windows::Forms::Label ^ label2;
      System::Windows::Forms::Label ^ label3;
      System::Windows::Forms::Label ^ label4;
      System::Windows::Forms::Label ^ label5;
      System::Windows::Forms::Label ^ label6;
      System::Windows::Forms::Label ^ label7;
      System::Windows::Forms::Label ^ label8;
      System::Windows::Forms::Label ^ label9;
      System::Windows::Forms::Button^ clearButton;
      System::Drawing::Drawing2D::GraphicsPath^ mousePath;
      System::Windows::Forms::GroupBox^ groupBox1;
      int fontSize;

   public:
      Form1()
      {
         fontSize = 20;
         mousePath = gcnew System::Drawing::Drawing2D::GraphicsPath;
         this->panel1 = gcnew System::Windows::Forms::Panel;
         this->label1 = gcnew System::Windows::Forms::Label;
         this->clearButton = gcnew System::Windows::Forms::Button;
         this->label2 = gcnew System::Windows::Forms::Label;
         this->label3 = gcnew System::Windows::Forms::Label;
         this->label4 = gcnew System::Windows::Forms::Label;
         this->label5 = gcnew System::Windows::Forms::Label;
         this->label6 = gcnew System::Windows::Forms::Label;
         this->label7 = gcnew System::Windows::Forms::Label;
         this->label8 = gcnew System::Windows::Forms::Label;
         this->label9 = gcnew System::Windows::Forms::Label;
         this->groupBox1 = gcnew System::Windows::Forms::GroupBox;
         
         // Mouse Events Label
         this->label1->Location = System::Drawing::Point( 24, 504 );
         this->label1->Size = System::Drawing::Size( 392, 23 );
         
         // DoubleClickSize Label
         this->label2->AutoSize = true;
         this->label2->Location = System::Drawing::Point( 24, 48 );
         this->label2->Size = System::Drawing::Size( 35, 13 );
         
         // DoubleClickTime Label
         this->label3->AutoSize = true;
         this->label3->Location = System::Drawing::Point( 24, 72 );
         this->label3->Size = System::Drawing::Size( 35, 13 );
         
         // MousePresent Label
         this->label4->AutoSize = true;
         this->label4->Location = System::Drawing::Point( 24, 96 );
         this->label4->Size = System::Drawing::Size( 35, 13 );
         
         // MouseButtons Label
         this->label5->AutoSize = true;
         this->label5->Location = System::Drawing::Point( 24, 120 );
         this->label5->Size = System::Drawing::Size( 35, 13 );
         
         // MouseButtonsSwapped Label
         this->label6->AutoSize = true;
         this->label6->Location = System::Drawing::Point( 320, 48 );
         this->label6->Size = System::Drawing::Size( 35, 13 );
         
         // MouseWheelPresent Label
         this->label7->AutoSize = true;
         this->label7->Location = System::Drawing::Point( 320, 72 );
         this->label7->Size = System::Drawing::Size( 35, 13 );
         
         // MouseWheelScrollLines Label
         this->label8->AutoSize = true;
         this->label8->Location = System::Drawing::Point( 320, 96 );
         this->label8->Size = System::Drawing::Size( 35, 13 );
         
         // NativeMouseWheelSupport Label
         this->label9->AutoSize = true;
         this->label9->Location = System::Drawing::Point( 320, 120 );
         this->label9->Size = System::Drawing::Size( 35, 13 );
         
         // Mouse Panel
         this->panel1->Anchor = static_cast<System::Windows::Forms::AnchorStyles>(System::Windows::Forms::AnchorStyles::Top | System::Windows::Forms::AnchorStyles::Left | System::Windows::Forms::AnchorStyles::Right);
         this->panel1->BackColor = System::Drawing::SystemColors::ControlDark;
         this->panel1->Location = System::Drawing::Point( 16, 160 );
         this->panel1->Size = System::Drawing::Size( 664, 320 );
         this->panel1->MouseUp += gcnew System::Windows::Forms::MouseEventHandler( this, &Form1::panel1_MouseUp );
         this->panel1->Paint += gcnew System::Windows::Forms::PaintEventHandler( this, &Form1::panel1_Paint );
         this->panel1->MouseEnter += gcnew System::EventHandler( this, &Form1::panel1_MouseEnter );
         this->panel1->MouseHover += gcnew System::EventHandler( this, &Form1::panel1_MouseHover );
         this->panel1->MouseMove += gcnew System::Windows::Forms::MouseEventHandler( this, &Form1::panel1_MouseMove );
         this->panel1->MouseLeave += gcnew System::EventHandler( this, &Form1::panel1_MouseLeave );
         this->panel1->MouseDown += gcnew System::Windows::Forms::MouseEventHandler( this, &Form1::panel1_MouseDown );
         this->panel1->MouseWheel += gcnew System::Windows::Forms::MouseEventHandler( this, &Form1::panel1_MouseWheel );
         
         // Clear Button
         this->clearButton->Anchor = static_cast<System::Windows::Forms::AnchorStyles>(System::Windows::Forms::AnchorStyles::Top | System::Windows::Forms::AnchorStyles::Right);
         this->clearButton->Location = System::Drawing::Point( 592, 504 );
         this->clearButton->TabIndex = 1;
         this->clearButton->Text = "Clear";
         this->clearButton->Click += gcnew System::EventHandler( this, &Form1::clearButton_Click );
         
         // GroupBox
         this->groupBox1->Anchor = static_cast<System::Windows::Forms::AnchorStyles>(System::Windows::Forms::AnchorStyles::Top | System::Windows::Forms::AnchorStyles::Left | System::Windows::Forms::AnchorStyles::Right);
         this->groupBox1->Location = System::Drawing::Point( 16, 24 );
         this->groupBox1->Size = System::Drawing::Size( 664, 128 );
         this->groupBox1->Text = "System::Windows::Forms::SystemInformation";
         
         // Set up how the form should be displayed and add the controls to the form.
         this->ClientSize = System::Drawing::Size( 696, 534 );
         array<System::Windows::Forms::Control^>^temp0 = {this->label9,this->label8,this->label7,this->label6,this->label5,this->label4,this->label3,this->label2,this->clearButton,this->panel1,this->label1,this->groupBox1};
         this->Controls->AddRange( temp0 );
         this->Text = "Mouse Event Example";
         
         // Displays information about the system mouse.
         label2->Text = "SystemInformation::DoubleClickSize: {0}",SystemInformation::DoubleClickSize;
         label3->Text = "SystemInformation::DoubleClickTime: {0}",SystemInformation::DoubleClickTime;
         label4->Text = "SystemInformation::MousePresent: {0}",SystemInformation::MousePresent;
         label5->Text = "SystemInformation::MouseButtons: {0}",SystemInformation::MouseButtons;
         label6->Text = "SystemInformation::MouseButtonsSwapped: {0}",SystemInformation::MouseButtonsSwapped;
         label7->Text = "SystemInformation::MouseWheelPresent: {0}",SystemInformation::MouseWheelPresent;
         label8->Text = "SystemInformation::MouseWheelScrollLines: {0}",SystemInformation::MouseWheelScrollLines;
         label9->Text = "SystemInformation::NativeMouseWheelSupport: {0}",SystemInformation::NativeMouseWheelSupport;
      }

   private:
      void panel1_MouseDown( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
      {
         // Update the mouse path with the mouse information
         Point mouseDownLocation = Point(e->X,e->Y);
         String^ eventString = nullptr;
         switch ( e->Button )
         {
            case ::MouseButtons::Left:
               eventString = "L";
               break;

            case ::MouseButtons::Right:
               eventString = "R";
               break;

            case ::MouseButtons::Middle:
               eventString = "M";
               break;

            case ::MouseButtons::XButton1:
               eventString = "X1";
               break;

            case ::MouseButtons::XButton2:
               eventString = "X2";
               break;

            case ::MouseButtons::None:
            default:
               break;
         }
         if ( eventString != nullptr )
         {
            mousePath->AddString( eventString, FontFamily::GenericSerif, (int)FontStyle::Bold, (float)fontSize, mouseDownLocation, StringFormat::GenericDefault );
         }
         else
         {
            mousePath->AddLine( mouseDownLocation, mouseDownLocation );
         }

         panel1->Focus();
         panel1->Invalidate();
      }

      void panel1_MouseEnter( Object^ sender, System::EventArgs^ /*e*/ )
      {
         
         // Update the mouse event label to indicate the MouseEnter event occurred.
         label1->Text = String::Concat( sender->GetType(), ": MouseEnter" );
      }

      void panel1_MouseHover( Object^ sender, System::EventArgs^ /*e*/ )
      {
         
         // Update the mouse event label to indicate the MouseHover event occurred.
         label1->Text = String::Concat( sender->GetType(), ": MouseHover" );
      }

      void panel1_MouseLeave( Object^ sender, System::EventArgs^ /*e*/ )
      {
         
         // Update the mouse event label to indicate the MouseLeave event occurred.
         label1->Text = String::Concat( sender->GetType(), ": MouseLeave" );
      }

      void panel1_MouseMove( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
      {
         // Update the mouse path that is drawn onto the Panel.
         int mouseX = e->X;
         int mouseY = e->Y;
         mousePath->AddLine( mouseX, mouseY, mouseX, mouseY );
      }

      void panel1_MouseWheel( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
      {
         // Update the drawing based upon the mouse wheel scrolling.
         int numberOfTextLinesToMove = e->Delta * SystemInformation::MouseWheelScrollLines / 120;
         int numberOfPixelsToMove = numberOfTextLinesToMove * fontSize;
         if ( numberOfPixelsToMove != 0 )
         {
            System::Drawing::Drawing2D::Matrix^ translateMatrix = gcnew System::Drawing::Drawing2D::Matrix;
            translateMatrix->Translate( 0, (float)numberOfPixelsToMove );
            mousePath->Transform(translateMatrix);
         }

         panel1->Invalidate();
      }

      void panel1_MouseUp( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
      {
         Point mouseUpLocation = System::Drawing::Point( e->X, e->Y );
         
         // Show the number of clicks in the path graphic.
         int numberOfClicks = e->Clicks;
         mousePath->AddString( String::Format( "   {0}", numberOfClicks ), FontFamily::GenericSerif, (int)FontStyle::Bold, (float)fontSize, mouseUpLocation, StringFormat::GenericDefault );
         panel1->Invalidate();
      }

      void panel1_Paint( Object^ /*sender*/, System::Windows::Forms::PaintEventArgs^ e )
      {
         // Perform the painting of the Panel.
         e->Graphics->DrawPath( System::Drawing::Pens::DarkRed, mousePath );
      }

      void clearButton_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
      {
         // Clear the Panel display.
         delete mousePath;
         mousePath = gcnew System::Drawing::Drawing2D::GraphicsPath;
         panel1->Invalidate();
      }
   };
}

[STAThread]
int main()
{
   Application::Run( gcnew MouseEvent::Form1 );
}
using System;
using System.Drawing;
using System.Windows.Forms;

namespace MouseEvent
{
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.Panel panel1;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.Label label4;
        private System.Windows.Forms.Label label5;
        private System.Windows.Forms.Label label6;
        private System.Windows.Forms.Label label7;
        private System.Windows.Forms.Label label8;
        private System.Windows.Forms.Label label9;
        private System.Windows.Forms.Button clearButton;
        private System.Drawing.Drawing2D.GraphicsPath mousePath;
        private System.Windows.Forms.GroupBox groupBox1;

        private int fontSize = 20;        

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

        public Form1()
        {            
            mousePath = new System.Drawing.Drawing2D.GraphicsPath();

            this.panel1 = new System.Windows.Forms.Panel();
            this.label1 = new System.Windows.Forms.Label();
            this.clearButton = new System.Windows.Forms.Button();
            this.label2 = new System.Windows.Forms.Label();
            this.label3 = new System.Windows.Forms.Label();
            this.label4 = new System.Windows.Forms.Label();
            this.label5 = new System.Windows.Forms.Label();
            this.label6 = new System.Windows.Forms.Label();
            this.label7 = new System.Windows.Forms.Label();
            this.label8 = new System.Windows.Forms.Label();
            this.label9 = new System.Windows.Forms.Label();
            this.groupBox1 = new System.Windows.Forms.GroupBox();

            // Mouse Events Label
            this.label1.Location = new System.Drawing.Point(24, 504);
            this.label1.Size = new System.Drawing.Size(392, 23);
            // DoubleClickSize Label
            this.label2.AutoSize = true;
            this.label2.Location = new System.Drawing.Point(24, 48);
            this.label2.Size = new System.Drawing.Size(35, 13);
            // DoubleClickTime Label
            this.label3.AutoSize = true;
            this.label3.Location = new System.Drawing.Point(24, 72);
            this.label3.Size = new System.Drawing.Size(35, 13);
            // MousePresent Label
            this.label4.AutoSize = true;
            this.label4.Location = new System.Drawing.Point(24, 96);
            this.label4.Size = new System.Drawing.Size(35, 13);
            // MouseButtons Label
            this.label5.AutoSize = true;
            this.label5.Location = new System.Drawing.Point(24, 120);
            this.label5.Size = new System.Drawing.Size(35, 13);
            // MouseButtonsSwapped Label
            this.label6.AutoSize = true;
            this.label6.Location = new System.Drawing.Point(320, 48);
            this.label6.Size = new System.Drawing.Size(35, 13);
            // MouseWheelPresent Label
            this.label7.AutoSize = true;
            this.label7.Location = new System.Drawing.Point(320, 72);
            this.label7.Size = new System.Drawing.Size(35, 13);
            // MouseWheelScrollLines Label
            this.label8.AutoSize = true;
            this.label8.Location = new System.Drawing.Point(320, 96);
            this.label8.Size = new System.Drawing.Size(35, 13);
            // NativeMouseWheelSupport Label
            this.label9.AutoSize = true;
            this.label9.Location = new System.Drawing.Point(320, 120);
            this.label9.Size = new System.Drawing.Size(35, 13);

            // Mouse Panel
            this.panel1.Anchor = ((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
                | System.Windows.Forms.AnchorStyles.Right);
            this.panel1.BackColor = System.Drawing.SystemColors.ControlDark;
            this.panel1.Location = new System.Drawing.Point(16, 160);
            this.panel1.Size = new System.Drawing.Size(664, 320);
            this.panel1.MouseUp += new System.Windows.Forms.MouseEventHandler(this.panel1_MouseUp);
            this.panel1.Paint += new System.Windows.Forms.PaintEventHandler(this.panel1_Paint);
            this.panel1.MouseEnter += new System.EventHandler(this.panel1_MouseEnter);
            this.panel1.MouseHover += new System.EventHandler(this.panel1_MouseHover);
            this.panel1.MouseMove += new System.Windows.Forms.MouseEventHandler(this.panel1_MouseMove);
            this.panel1.MouseLeave += new System.EventHandler(this.panel1_MouseLeave);
            this.panel1.MouseDown += new System.Windows.Forms.MouseEventHandler(this.panel1_MouseDown);
            this.panel1.MouseWheel += new System.Windows.Forms.MouseEventHandler(this.panel1_MouseWheel);

            // Clear Button
            this.clearButton.Anchor = (System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right);
            this.clearButton.Location = new System.Drawing.Point(592, 504);
            this.clearButton.TabIndex = 1;
            this.clearButton.Text = "Clear";
            this.clearButton.Click += new System.EventHandler(this.clearButton_Click);
            
            // GroupBox
            this.groupBox1.Anchor = ((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
                | System.Windows.Forms.AnchorStyles.Right);
            this.groupBox1.Location = new System.Drawing.Point(16, 24);
            this.groupBox1.Size = new System.Drawing.Size(664, 128);
            this.groupBox1.Text = "System.Windows.Forms.SystemInformation";

            // Set up how the form should be displayed and add the controls to the form.
            this.ClientSize = new System.Drawing.Size(696, 534);
            this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                        this.label9,this.label8,this.label7,this.label6,
                                        this.label5,this.label4,this.label3,this.label2,
                                        this.clearButton,this.panel1,this.label1,this.groupBox1});
            this.Text = "Mouse Event Example";

            // Displays information about the system mouse.
            label2.Text = "SystemInformation.DoubleClickSize: " + SystemInformation.DoubleClickSize.ToString();
            label3.Text = "SystemInformation.DoubleClickTime: " + SystemInformation.DoubleClickTime.ToString();
            label4.Text = "SystemInformation.MousePresent: " + SystemInformation.MousePresent.ToString();
            label5.Text = "SystemInformation.MouseButtons: " + SystemInformation.MouseButtons.ToString();
            label6.Text = "SystemInformation.MouseButtonsSwapped: " + SystemInformation.MouseButtonsSwapped.ToString();
            label7.Text = "SystemInformation.MouseWheelPresent: " + SystemInformation.MouseWheelPresent.ToString();
            label8.Text = "SystemInformation.MouseWheelScrollLines: " + SystemInformation.MouseWheelScrollLines.ToString();
            label9.Text = "SystemInformation.NativeMouseWheelSupport: " + SystemInformation.NativeMouseWheelSupport.ToString();

        }

        private void panel1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e) 
        {
            // Update the mouse path with the mouse information
            Point mouseDownLocation = new Point(e.X, e.Y);

            string eventString = null;
            switch (e.Button) {
                case MouseButtons.Left:
                    eventString = "L";
                    break;
                case MouseButtons.Right:
                    eventString = "R";
                    break;
                case MouseButtons.Middle:
                    eventString = "M";
                    break;
                case MouseButtons.XButton1:
                    eventString = "X1";
                    break;
                case MouseButtons.XButton2:
                    eventString = "X2";
                    break;
                case MouseButtons.None:
                default:
                    break;
            }

            if (eventString != null) 
            {
                mousePath.AddString(eventString, FontFamily.GenericSerif, (int)FontStyle.Bold, fontSize, mouseDownLocation, StringFormat.GenericDefault);
            }
            else 
            {
                mousePath.AddLine(mouseDownLocation,mouseDownLocation);
            }
            panel1.Focus();
            panel1.Invalidate();
        }

        private void panel1_MouseEnter(object sender, System.EventArgs e) 
        {
            // Update the mouse event label to indicate the MouseEnter event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseEnter";
        }

        private void panel1_MouseHover(object sender, System.EventArgs e) 
        {
            // Update the mouse event label to indicate the MouseHover event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseHover";
        }

        private void panel1_MouseLeave(object sender, System.EventArgs e) 
        {
            // Update the mouse event label to indicate the MouseLeave event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseLeave";
        }

        private void panel1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            // Update the mouse path that is drawn onto the Panel.
            int mouseX = e.X;
            int mouseY = e.Y;
            
            mousePath.AddLine(mouseX,mouseY,mouseX,mouseY);
        }

        private void panel1_MouseWheel(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            // Update the drawing based upon the mouse wheel scrolling.
      
            int numberOfTextLinesToMove = e.Delta * SystemInformation.MouseWheelScrollLines / 120;
            int numberOfPixelsToMove = numberOfTextLinesToMove * fontSize;

            if (numberOfPixelsToMove != 0) {
                System.Drawing.Drawing2D.Matrix translateMatrix = new  System.Drawing.Drawing2D.Matrix();
                translateMatrix.Translate(0, numberOfPixelsToMove);
                mousePath.Transform(translateMatrix);
            }
            panel1.Invalidate();
        }
        private void panel1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e) 
        {
            Point mouseUpLocation = new System.Drawing.Point(e.X, e.Y);
        
            // Show the number of clicks in the path graphic.
            int numberOfClicks = e.Clicks;
            mousePath.AddString("    " + numberOfClicks.ToString(), 
                        FontFamily.GenericSerif, (int)FontStyle.Bold, 
                        fontSize, mouseUpLocation, StringFormat.GenericDefault);

            panel1.Invalidate();
        }

        private void panel1_Paint(object sender, System.Windows.Forms.PaintEventArgs e) 
        {    
            // Perform the painting of the Panel.
            e.Graphics.DrawPath(System.Drawing.Pens.DarkRed, mousePath);
        }

        private void clearButton_Click(object sender, System.EventArgs e)
        {
            // Clear the Panel display.
            mousePath.Dispose();
            mousePath = new System.Drawing.Drawing2D.GraphicsPath();
            panel1.Invalidate();
        }
    }
}
Imports System.Drawing
Imports System.Windows.Forms

Namespace MouseEvent
    ' Summary description for Form1.
    Public NotInheritable Class Form1
        Inherits System.Windows.Forms.Form

        Friend WithEvents panel1 As System.Windows.Forms.Panel
        Private label1 As System.Windows.Forms.Label
        Private label2 As System.Windows.Forms.Label
        Private label3 As System.Windows.Forms.Label
        Private label4 As System.Windows.Forms.Label
        Private label5 As System.Windows.Forms.Label
        Private label6 As System.Windows.Forms.Label
        Private label7 As System.Windows.Forms.Label
        Private label8 As System.Windows.Forms.Label
        Private label9 As System.Windows.Forms.Label
        Friend WithEvents clearButton As System.Windows.Forms.Button
        Private mousePath As System.Drawing.Drawing2D.GraphicsPath
        Private groupBox1 As System.Windows.Forms.GroupBox

        Private fontSize As Integer = 20
        
        <System.STAThread()>  _
        Public Shared Sub Main()
            System.Windows.Forms.Application.Run(New Form1())
        End Sub

        Public Sub New()

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

            Me.panel1 = New System.Windows.Forms.Panel()
            Me.label1 = New System.Windows.Forms.Label()
            Me.clearButton = New System.Windows.Forms.Button()
            Me.label2 = New System.Windows.Forms.Label()
            Me.label3 = New System.Windows.Forms.Label()
            Me.label4 = New System.Windows.Forms.Label()
            Me.label5 = New System.Windows.Forms.Label()
            Me.label6 = New System.Windows.Forms.Label()
            Me.label7 = New System.Windows.Forms.Label()
            Me.label8 = New System.Windows.Forms.Label()
            Me.label9 = New System.Windows.Forms.Label()
            Me.groupBox1 = New System.Windows.Forms.GroupBox()

            ' Mouse Events Label
            Me.label1.Location = New System.Drawing.Point(24, 504) 
            Me.label1.Size = New System.Drawing.Size(392, 23) 
            ' DoubleClickSize Label
            Me.label2.AutoSize = True 
            Me.label2.Location = New System.Drawing.Point(24, 48) 
            Me.label2.Size = New System.Drawing.Size(35, 13) 
            ' DoubleClickTime Label
            Me.label3.AutoSize = True 
            Me.label3.Location = New System.Drawing.Point(24, 72) 
            Me.label3.Size = New System.Drawing.Size(35, 13) 
            ' MousePresent Label
            Me.label4.AutoSize = True 
            Me.label4.Location = New System.Drawing.Point(24, 96) 
            Me.label4.Size = New System.Drawing.Size(35, 13) 
            ' MouseButtons Label
            Me.label5.AutoSize = True 
            Me.label5.Location = New System.Drawing.Point(24, 120) 
            Me.label5.Size = New System.Drawing.Size(35, 13) 
            ' MouseButtonsSwapped Label
            Me.label6.AutoSize = True 
            Me.label6.Location = New System.Drawing.Point(320, 48) 
            Me.label6.Size = New System.Drawing.Size(35, 13) 
            ' MouseWheelPresent Label
            Me.label7.AutoSize = True 
            Me.label7.Location = New System.Drawing.Point(320, 72) 
            Me.label7.Size = New System.Drawing.Size(35, 13) 
            ' MouseWheelScrollLines Label
            Me.label8.AutoSize = True 
            Me.label8.Location = New System.Drawing.Point(320, 96) 
            Me.label8.Size = New System.Drawing.Size(35, 13) 
            ' NativeMouseWheelSupport Label
            Me.label9.AutoSize = True 
            Me.label9.Location = New System.Drawing.Point(320, 120) 
            Me.label9.Size = New System.Drawing.Size(35, 13) 

            ' Mouse Panel
            Me.panel1.Anchor = System.Windows.Forms.AnchorStyles.Top Or _
                                    System.Windows.Forms.AnchorStyles.Left Or _
                                    System.Windows.Forms.AnchorStyles.Right
            Me.panel1.BackColor = System.Drawing.SystemColors.ControlDark
            Me.panel1.Location = New System.Drawing.Point(16, 160)
            Me.panel1.Size = New System.Drawing.Size(664, 320)

            ' Clear Button
            Me.clearButton.Anchor = System.Windows.Forms.AnchorStyles.Top Or _
                                    System.Windows.Forms.AnchorStyles.Right
            Me.clearButton.Location = New System.Drawing.Point(592, 504)
            Me.clearButton.TabIndex = 1
            Me.clearButton.Text = "Clear"

            ' GroupBox
            Me.groupBox1.Anchor = System.Windows.Forms.AnchorStyles.Top Or _
                                  System.Windows.Forms.AnchorStyles.Left Or _
                                  System.Windows.Forms.AnchorStyles.Right
            Me.groupBox1.Location = New System.Drawing.Point(16, 24)
            Me.groupBox1.Size = New System.Drawing.Size(664, 128)
            Me.groupBox1.Text = "System.Windows.Forms.SystemInformation"

            ' Set up how the form should be displayed and add the controls to the form.
            Me.ClientSize = New System.Drawing.Size(696, 534)
            Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.label9, _
                            Me.label8, Me.label7, Me.label6, Me.label5, Me.label4, _
                            Me.label3, Me.label2, Me.clearButton, Me.panel1, Me.label1, Me.groupBox1})

            Me.Text = "Mouse Event Example"

            ' Display information about the system mouse.
            label2.Text = "SystemInformation.DoubleClickSize: " + SystemInformation.DoubleClickSize.ToString()
            label3.Text = "SystemInformation.DoubleClickTime: " + SystemInformation.DoubleClickTime.ToString()
            label4.Text = "SystemInformation.MousePresent: " + SystemInformation.MousePresent.ToString()
            label5.Text = "SystemInformation.MouseButtons: " + SystemInformation.MouseButtons.ToString()
            label6.Text = "SystemInformation.MouseButtonsSwapped: " + SystemInformation.MouseButtonsSwapped.ToString()
            label7.Text = "SystemInformation.MouseWheelPresent: " + SystemInformation.MouseWheelPresent.ToString()
            label8.Text = "SystemInformation.MouseWheelScrollLines: " + SystemInformation.MouseWheelScrollLines.ToString()
            label9.Text = "SystemInformation.NativeMouseWheelSupport: " + SystemInformation.NativeMouseWheelSupport.ToString()
        End Sub

        Private Sub panel1_MouseDown(sender As Object, e As System.Windows.Forms.MouseEventArgs) Handles panel1.MouseDown
            ' Update the mouse path with the mouse information
            Dim mouseDownLocation As New Point(e.X, e.Y)
            
            Dim eventString As String = Nothing
            Select Case e.Button
                Case MouseButtons.Left
                    eventString = "L"
                Case MouseButtons.Right
                    eventString = "R"
                Case MouseButtons.Middle
                    eventString = "M"
                Case MouseButtons.XButton1
                    eventString = "X1"
                Case MouseButtons.XButton2
                    eventString = "X2"
                Case MouseButtons.None:
                     eventString = Nothing              
            End Select
            
            If (eventString IsNot Nothing) Then
                mousePath.AddString(eventString, FontFamily.GenericSerif, CInt(FontStyle.Bold), fontSize, mouseDownLocation, StringFormat.GenericDefault)
            Else
                mousePath.AddLine(mouseDownLocation, mouseDownLocation)
            End If

            panel1.Focus()
            panel1.Invalidate()
        End Sub 
        
        Private Sub panel1_MouseEnter(sender As Object, e As System.EventArgs) Handles panel1.MouseEnter
            ' Update the mouse event label to indicate the MouseEnter event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseEnter"
        End Sub
        
        Private Sub panel1_MouseHover(sender As Object, e As System.EventArgs) Handles panel1.MouseHover
            ' Update the mouse event label to indicate the MouseHover event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseHover"
        End Sub
        
        Private Sub panel1_MouseLeave(sender As Object, e As System.EventArgs) Handles panel1.MouseLeave
            ' Update the mouse event label to indicate the MouseLeave event occurred.
            label1.Text = sender.GetType().ToString() + ": MouseLeave"
        End Sub
        
        Private Sub panel1_MouseMove(sender As Object, e As System.Windows.Forms.MouseEventArgs) Handles panel1.MouseMove
            ' Update the mouse path that is drawn onto the Panel.
            Dim mouseX As Integer = e.X
            Dim mouseY As Integer = e.Y
            
            mousePath.AddLine(mouseX, mouseY, mouseX, mouseY)
        End Sub
        Private Sub panel1_MouseWheel(sender As Object, e As System.Windows.Forms.MouseEventArgs) Handles panel1.MouseWheel
            ' Update the drawing based upon the mouse wheel scrolling.
            Dim numberOfTextLinesToMove As Integer = CInt(e.Delta * SystemInformation.MouseWheelScrollLines / 120) 
            Dim numberOfPixelsToMove As Integer = numberOfTextLinesToMove * fontSize
            
            If numberOfPixelsToMove <> 0 Then
                Dim translateMatrix As New System.Drawing.Drawing2D.Matrix()
                translateMatrix.Translate(0, numberOfPixelsToMove)
                mousePath.Transform(translateMatrix)
            End If

            panel1.Invalidate()
        End Sub
        Private Sub panel1_MouseUp(sender As Object, e As System.Windows.Forms.MouseEventArgs) Handles panel1.MouseUp
            Dim mouseUpLocation As New System.Drawing.Point(e.X, e.Y)
            
            ' Show the number of clicks in the path graphic.
            Dim numberOfClicks As Integer = e.Clicks
            mousePath.AddString("     " + numberOfClicks.ToString(), _
                                FontFamily.GenericSerif, CInt(FontStyle.Bold), _
                                fontSize, mouseUpLocation, StringFormat.GenericDefault)

            panel1.Invalidate()
        End Sub
        
        Private Sub panel1_Paint(sender As Object, e As System.Windows.Forms.PaintEventArgs) Handles panel1.Paint
            ' Perform the painting of the Panel.
            e.Graphics.DrawPath(System.Drawing.Pens.DarkRed, mousePath)
        End Sub
        
        Private Sub clearButton_Click(sender As Object, e As System.EventArgs) Handles clearButton.Click
            ' Clear the Panel display.
            mousePath.Dispose()
            mousePath = New System.Drawing.Drawing2D.GraphicsPath()
            panel1.Invalidate()
        End Sub
        
    End Class
End Namespace

Comentarios

Al controlar el evento MouseWheel es importante seguir los estándares de la interfaz de usuario (IU) asociados a la rueda del mouse.When handling the MouseWheel event it is important to follow the user interface (UI) standards associated with the mouse wheel. El valor de la propiedad MouseEventArgs.Delta indica la cantidad de movimiento de la rueda del mouse.The MouseEventArgs.Delta property value indicates the amount the mouse wheel has been moved. La interfaz de usuario debe desplazarse cuando el Delta acumulado es más o menos 120.The UI should scroll when the accumulated delta is plus or minus 120. La interfaz de usuario debe desplazarse por el número de líneas lógicas devueltas por la propiedad SystemInformation.MouseWheelScrollLines para cada valor de incremento alcanzado.The UI should scroll the number of logical lines returned by the SystemInformation.MouseWheelScrollLines property for every delta value reached. También puede desplazarse con mayor suavidad en los incrementos de unidades de 120, sin embargo, la relación debe permanecer constante, es decir, SystemInformation.MouseWheelScrollLines líneas desplazadas por unidades Delta de 120 de movimiento de la rueda.You can also scroll more smoothly in smaller that 120 unit increments, however the ratio should remain constant, that is SystemInformation.MouseWheelScrollLines lines scrolled per 120 delta units of wheel movement.

Para obtener más información sobre cómo controlar los mensajes de la rueda del mouse, vea el tema WM_MOUSEWHEEL .For more information about handling mouse wheel messages, see the WM_MOUSEWHEEL topic.

Los eventos del mouse se producen en el siguiente orden:Mouse events occur in the following order:

  1. MouseEnter

  2. MouseMove

  3. MouseHover / MouseDown / MouseWheel

  4. MouseUp

  5. MouseLeave

Para obtener más información sobre el manejo de eventos, consulte controlar y provocar eventos.For more information about handling events, see Handling and Raising Events.

Se aplica a

Consulte también: