如何区分单击和双击事件

当我们做Winform项目的时候，有可能会遇到这样的需求，当一个控件上既绑定了单击事件又绑定了双击事件，这样就会遇到一个问题，我们的双击事件没有触发之前，往往先触发了单击事件，影响到了用户的操作。如果让系统区分用户是进行了单击还是双击事件，就显得非常必要了。

我们看一下微软上面是不是有解决办法。

混滚点击操作

using System;
using System.ComponentModel;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace MouseRollBackSingleClick
{
public class Form1 : Form
{
private DoubleClickButton button1;
private FormBorderStyle initialStyle;

public Form1()
{
initialStyle = this.FormBorderStyle;
this.ClientSize = new System.Drawing.Size(292, 266);
button1 = new DoubleClickButton();
button1.Location = new Point (40,40);
button1.Click += new EventHandler(button1_Click);
button1.AutoSize = true;
this.AllowDrop = true;
button1.Text = "Click or Double Click";
button1.DoubleClick += new EventHandler(button1_DoubleClick);
this.Controls.Add(button1);

}

// Handle the double click event.
void button1_DoubleClick(object sender, EventArgs e)
{
// Change the border style back to the initial style.
this.FormBorderStyle = initialStyle;
MessageBox.Show("Rolled back single click change.");
}

// Handle the click event.
void button1_Click(object sender, EventArgs e)
{
this.FormBorderStyle = FormBorderStyle.FixedToolWindow;
}

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

}
public class DoubleClickButton : Button
{
public DoubleClickButton() : base()
{
// Set the style so a double click event occurs.
SetStyle(ControlStyles.StandardClick |
ControlStyles.StandardDoubleClick, true);
}
}
}

区分MouseDown事件中的点击次数

using System;
using System.Drawing;
using System.Windows.Forms;

namespace SingleVersusDoubleClick
{
class Form1 : Form
{
private Rectangle hitTestRectangle = new Rectangle();
private Rectangle doubleClickRectangle = new Rectangle();
private TextBox textBox1 = new TextBox();
private Timer doubleClickTimer = new Timer();
private ProgressBar doubleClickBar = new ProgressBar();
private Label label1 = new Label();
private Label label2 = new Label();
private bool isFirstClick = true;
private bool isDoubleClick = false;
private int milliseconds = 0;

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

public Form1()
{
label1.Location = new Point(30, 5);
label1.Size = new Size(100, 15);
label1.Text = "Hit test rectangle:";

label2.Location = new Point(30, 70);
label2.Size = new Size(100, 15);
label2.Text = "Double click timer:";

hitTestRectangle.Location = new Point(30, 20);
hitTestRectangle.Size = new Size(100, 40);

doubleClickTimer.Interval = 100;
doubleClickTimer.Tick +=
new EventHandler(doubleClickTimer_Tick);

doubleClickBar.Location = new Point(30, 85);
doubleClickBar.Minimum = 0;
doubleClickBar.Maximum = SystemInformation.DoubleClickTime;

textBox1.Location = new Point(30, 120);
textBox1.Size = new Size(200, 100);
textBox1.AutoSize = false;
textBox1.Multiline = true;

this.Paint += new PaintEventHandler(Form1_Paint);
this.MouseDown += new MouseEventHandler(Form1_MouseDown);
this.Controls.AddRange(new Control[] { doubleClickBar, textBox1,
label1, label2 });
}

// Detect a valid single click or double click.
void Form1_MouseDown(object sender, MouseEventArgs e)
{
// Verify that the mouse click is in the main hit
// test rectangle.
if (!hitTestRectangle.Contains(e.Location))
{
return;
}

// This is the first mouse click.
if (isFirstClick)
{
isFirstClick = false;

// Determine the location and size of the double click
// rectangle area to draw around the cursor point.
doubleClickRectangle = new Rectangle(
e.X - (SystemInformation.DoubleClickSize.Width / 2),
e.Y - (SystemInformation.DoubleClickSize.Height / 2),
SystemInformation.DoubleClickSize.Width,
SystemInformation.DoubleClickSize.Height);
Invalidate();

// Start the double click timer.
doubleClickTimer.Start();
}

// This is the second mouse click.
else
{
// Verify that the mouse click is within the double click
// rectangle and is within the system-defined double
// click period.
if (doubleClickRectangle.Contains(e.Location) &&
milliseconds < SystemInformation.DoubleClickTime)
{
isDoubleClick = true;
}
}
}

void doubleClickTimer_Tick(object sender, EventArgs e)
{
milliseconds += 100;
doubleClickBar.Increment(100);

// The timer has reached the double click time limit.
if (milliseconds >= SystemInformation.DoubleClickTime)
{
doubleClickTimer.Stop();

if (isDoubleClick)
{
textBox1.AppendText("Perform double click action");
textBox1.AppendText(Environment.NewLine);
}
else
{
textBox1.AppendText("Perform single click action");
textBox1.AppendText(Environment.NewLine);
}

// Allow the MouseDown event handler to process clicks again.
isFirstClick = true;
isDoubleClick = false;
milliseconds = 0;
doubleClickBar.Value = 0;
}
}

// Paint the hit test and double click rectangles.
void Form1_Paint(object sender, PaintEventArgs e)
{
// Draw the border of the main hit test rectangle.
e.Graphics.DrawRectangle(Pens.Black, hitTestRectangle);

// Fill in the double click rectangle.
e.Graphics.FillRectangle(Brushes.Blue, doubleClickRectangle);
}
}
}

这些例子要求：对System，System.Drawing和System.Windows.Forms程序集的引用。