How to: Create a Custom Double-Click Event
The .NET Compact Framework does not support the Windows Forms DoubleClick event for a button. But you can create a control that derives from the Button class to implement the event.
To create a custom double-click event
Create a class that derives from the System.Windows.Forms.Button class.
Declare a DoubleClick event.
Override the OnClick method with code to raise the DoubleClick event if button clicks occur within a specified time.
Example
This example creates a DoubleClickButton custom control and implements it on a form.
using System;
using System.Windows.Forms;
using System.Drawing;
namespace ButtonDClick
{
public class Form1 : System.Windows.Forms.Form
{
// Track the number of
// double-clicks with the count variable.
int count = 0;
public Form1()
{
InitializeComponent();
// Display OK button for closing.
this.MinimizeBox = false;
// Create an instance of the DoubleClickButton class.
DoubleClickButton dClickB = new DoubleClickButton();
dClickB.Bounds = new Rectangle(10,10,200,30);
dClickB.Text = "Double-click me!";
Controls.Add(dClickB);
// Add the DClick event hander to the DoubleClick event.
dClickB.DoubleClick += new EventHandler(DClick);
}
protected override void Dispose( bool disposing )
{
base.Dispose( disposing );
}
private void InitializeComponent()
{
this.Text = "Form1";
}
private void DClick(object o, EventArgs e)
{
// Display the number of double-clicks.
MessageBox.Show("Double-click count = " + ++count);
}
static void Main()
{
Application.Run(new Form1());
}
// Derive a button with extended funtionality
// from the Button class.
public class DoubleClickButton : System.Windows.Forms.Button
{
// Note that the DoubleClickTime property gets
// the maximum number of milliseconds allowed between
// mouse clicks for a double-click to be valid.
int previousClick = SystemInformation.DoubleClickTime;
public new event EventHandler DoubleClick;
protected override void OnClick(EventArgs e)
{
int now = System.Environment.TickCount;
// A double-click is detected if the the time elapsed
// since the last click is within DoubleClickTime.
if ( now - previousClick <= SystemInformation.DoubleClickTime)
{
// Raise the DoubleClick event.
if (DoubleClick != null)
DoubleClick(this,EventArgs.Empty);
}
// Set previousClick to now so that
// subsequent double-clicks can be detected.
previousClick = now;
// Allow the base class to raise the regular Click event.
base.OnClick(e);
}
// Event handling code for the DoubleClick event.
protected new virtual void OnDoubleClick(EventArgs e)
{
if (this.DoubleClick != null)
this.DoubleClick(this, e);
}
}
}
}
Compiling the Code
This example requires references to the following namespaces: