Control.MouseDown Event

public:
 event System::Windows::Forms::MouseEventHandler ^ MouseDown;

public event System.Windows.Forms.MouseEventHandler MouseDown;

public event System.Windows.Forms.MouseEventHandler? MouseDown;

member this.MouseDown : System.Windows.Forms.MouseEventHandler 

Public Custom Event MouseDown As MouseEventHandler 

Event Type

Examples

The following code example demonstrates using different mouse events to draw the path of the mouse on a Panel. A line segment is added to the GraphicsPath for each MouseMove and MouseDown events that occur. To update the graphics, the Invalidate method is called for the Panel on each MouseDown and MouseUp event. In addition, the graphic path is scrolled up or down when the MouseWheel event occurs. Additional mouse events, like MouseHover, are identified on screen as well. 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

Remarks

Mouse events occur in the following order:

1. MouseEnter

2. MouseMove

3. MouseHover / MouseDown / MouseWheel

4. MouseUp

5. MouseLeave

For more information about handling events, see Handling and Raising Events.

See also

• OnMouseDown(MouseEventArgs)
• MouseClick
• MouseUp
• MouseEventArgs