The Command Button's KeyPress
KeyDown and KeyUp Events
The events that will be mentioned in the following pages
are commonly used, and without learning about them you really
can't go anywhere in Visual Basic programming.
To try these examples, start a new
project (as being taught in lesson 1).
Add 1 Command Button to your form. The Command Button is called
by default Command1.
Copy the following code to the code window (you can copy and paste
it using Ctrl + C for copying and Ctrl + V for pasting):
Private Sub Command1_KeyDown(KeyCode
As Integer, Shift As Integer)
Print "KeyDown"
End Sub
Private Sub Command1_KeyPress(KeyAscii
As Integer)
Print "KeyPress"
End Sub
Private Sub Command1_KeyUp(KeyCode
As Integer, Shift As Integer)
Print "KeyUp"
End Sub
When the Command Button's KeyDown event will be executed,"KeyDown"
will be printed on the form,When the Command Button's KeyPress
event will be executed,"KeyPress"
will be printed on the form, and when the Command Button's KeyUp
event will be executed,
"KeyUp" will be printed on the form.
Run the program, and click the button with the mouse.Nothing has
happened.It's because the KeyDown, Key_Press, and KeyUp events
arebeing executed Only when you press a key on the keyboard.
Now press any key on the keyboard, hold it down for few seconds,and
then release it.
Your form will look like this:
 |
Lets see:
The first event that been executed
is the KeyDown event,becuase "KeyDown" was the first text that
been printed on the form.
The second event was KeyPress, and
then again KeyDown.After every KeyDown event that been executed,
a KeyPress event had been executed.
We learnt that when a key is being holded down, the KeyDown and
the KeyPress events are being executed in this order over and
over again, until the key is up again.When you release the key,
the KeyUp event is being executed once.