Conditional Statements Tutorial
Using The "Not"
Operator
The "Not" operator has very simple
function:
Not True = False
Not False = True
Before we continue,
I'll mention
that you don't have to include
"Else" in the "If" statement.
For example:
Dim Password As String
Password =
InputBox("Please enter the password")
If (Password = "let me in")
Then
MsgBox "The Password is correct!"
End If
If
the password is correct, The code above
will display a message box with the
text
"The Password is correct!".
Otherwise, the code will do
nothing,
because there is no "Else".
Lets see an example of using
the operator "Not".
Copy the following code to your Form_Load
event:
Dim Password As String
Password = InputBox("Please enter the
password")
If Not (Password = "let me in") Then
MsgBox
"Incorrect Password!"
End
End If
The boolean
expression: Not (Password = "let me in")
is True only if the Password is not "let
me in". Why?
If the Password is not "let me in",
(Password = "let me in") is False (Figure 3)
,
and we get the boolean expression: Not (False).
Not False =
True, so eventually, the
expression value is
True (Figure 3).
Figure 3
| Not |
(Password = "let me in") |
Not |
False |
True |
In conclusion,
The code
above will display a message box
with the text "Incorrect Password!" ONLY if
the password
is different from "let me in"