How to Distinguish a DblClick from a Click Event

MORE INFORMATION

Step-by-Step Example

1. Start a new project in Visual Basic. Form1 is created by default.
2. Add a Timer control (Timer1) to Form1.
3. Add the following code to the (general) (declarations) section of Form1:

      ' The following Function gets the DoubleClickSpeed from the WIN.INI
      ' file. Windows uses this setting to determine how close together two
      ' consecutive mouse clicks must occur for it to be interpreted as
      ' a double-click.
      ' Enter the following Declare statement on one, single line:
      Declare Function GetProfileInt% Lib "Kernel" (ByVal lpAppName$,
         ByVal lpKeyName$, ByVal nDefault%)
   						

4. Add the following code to the specified event procedures:

      Sub Form_Load ()
         clickSpeed% = GetProfileInt("Windows", "DoubleClickSpeed", 0)
         Timer1.Enabled = False         ' Timer should be off to begin with.
         Timer1.Interval = clickSpeed%  ' After the timer is turned on
                                        ' it will trigger the Timer Event
                                        ' after a specific amount of time
                                        ' equal to that of DoubleClickSpeed.
      End Sub
   
      Sub Form_Click ()
         Timer1.Enabled = True          ' Turn the timer on. If another mouse
                                        ' click does not occur within the
                                        ' DoubleClickSpeed interval, the
                                        ' Timer1_Timer Event will fire.
      End Sub
   
      Sub Form_DblClick ()
         Timer1.Enabled = False         ' Turn off the timer. This
                                        ' prevents the Timer1_Timer event
                                        ' from firing and thus the code
                                        ' for a single click will not be
                                        ' processed.
         Print "This is a double-click" ' Code for double-click goes here.
      End Sub
   
      Sub Timer1_Timer ()
         ' If this event occurs then there has not been another mouse
         ' click since the previous one within the DoubleClickSpeed
         ' time interval. Thus there will be two Click events rather
         ' than a DblClick Event.
         Timer1.Enabled = False         ' Turn off the timer so the
                                        ' Timer1_Timer Event does not
                                        ' continue to fire.
         Print "This is a Single Click" ' Code for single click goes here.
      End Sub
   						

5. Run the program.
6. Click once, wait a while, click again to receive two single clicks.
7. Click twice quickly to receive a double-click with no preceding single click.