beginners tutorial - Learn VB6
VB6 tutorial - Learn Advanced VB6
Analysis - System analysis and Design tutorial for Software Engineering
You are here: Visual
Basic > Advanced VB6 tutorial
> Chapter 5
KeyPress Versus KeyUp and KeyDown in Visual Basic 6
KeyDown and KeyUp don't detect exactly the same information as
KeyPress detects a character in its KeyAscii parameter, but KeyDown
and KeyUp detect a physical keystroke in their KeyCode parameter. While the difference
may seem subtle, it's a difference with practical consequences:
KeyUp and KeyDown can detect keystrokes
not recognized by KeyPress, such as function,
editing, and navigation keys.
KeyPress can distinguish between different
ASCII characters generated by the same physical
keystroke. For instance, KeyPress'
KeyAscii parameter gives two different values
for "A" and "a."
On the other hand, KeyUp and KeyDown's
KeyCode parameter gives only one value for
these two characters since the physical
keystroke is the same (Of course with a
little extra logic, you could use the Shift
parameter to figure out whether the Shift
key were being held). In addition, different
countryspecific keyboard mappings will generate
difference ASCII codes for the same physical
You should use KeyDown or KeyUp when you
need to detect keystrokes that don't
necessarily have an ASCII representation,
such as the function keys or the arrow keys,
or whenever you are interested in the physical
keystroke as such.
When you're interested in the actual
character that was generated by the keystroke,
you should use KeyPress.
NOTE: The Caps Lock Key The Caps Lock key generates
its own KeyDown and KeyUp events.
Keystroke Events at Field and Form Level topics
<< Previous | Contents
| Next >>