More
About Ascii
How can I know
what is the Ascii value of a specific character?
Use the Asc command.
For
example, the following line:
Print Asc("b")
Will print on the form the Ascii value of the character
"b".
How can I know which character's Ascii value is
98?
Use the Chr command.
For example, the following
line:
Print Chr(98)
Will print on the form
the character that its Ascii value is 98.
Learning about Parameters
(Continue)
Look at the first line of the Command Button's
KeyDown Event:
Private Sub Command1_KeyDown(KeyCode As Integer, Shift As
Integer)
As you can see,
the KeyDown event gets two parameters:
The KeyCode parameter, and the Shift
parameter, both are
Integer type.
Every Sub can get no parameters
(like the Click event), can get
one parameter (like the KeyPress event) or
can get more than
one parameter.
If a sub is getting more than one
parameter, the parameters
have to be separated with commas.
For example:
Private Sub MySubName (Parameter1 As
String, Parameter2 As Integer, Parameter3 As String)
Lets check out the
KeyDown event's parameters.
The first is KeyCode, and it holds the
KeyCode value
of the pressed key.
The KeyCode value is usually different
from the Ascii Value.
The different between KeyCode and Ascii, is
that
every character has Ascii value (for example G, @, |, =, and
more)
but there are some keys that don't represent any character, for
example:
Alt, F4, Ctrl, The left arrow key.
These keys don't have
Ascii value, but they have KeyCode value.
For example, the KeyCode value of
the Ctrl Key is 17.
Ascii
represent characters, while KeyCode represent Keyboard's keys.
Because of
that, the characters "a" and "A" have different Ascii value,
but they have
the same KeyCode value, because the same key
is typing "a" and
"A".
The second parameter is Shift, and its value helps you
to
determine if the user has pressed the Shift, Ctrl or Alt keys.
The Shift
holds the value 1 if the user has pressed the Shift key,
the value 2 if
the user has pressed the Ctrl Key,
and the value 4 if the user has pressed
the Alt Key.
If the user has pressed the Alt key and the Shift key
together,
the Shift value will be 4 (for the Alt key) + 1 (for the Shift key)
= 5
Examples:
If the user has pressed the "A" key,
The
KeyCode parameter will hold the number 65, and
the Shift parameter will
hold the value 0.
If the user has pressed Shift and "A" together,
The
KeyCode parameter will hold the number 65, and
the Shift parameter will hold the value
1.
The KeyUp event's parameters are the same as the
KeyDown event's parameters.
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