Name
#Const Directive
Syntax
#Constconstantname
=
expression
-
constantname
(required; String literal) Name of the constant
-
expression
(required; literal) Any combination of literal values, other conditional compilation constants defined with the
#Const
directive, and arithmetic or logical operators exceptIs
Description
Defines a conditional compiler constant.
By using compiler constants to create code blocks that are included in the compiled application only when a particular condition is met, you can create more than one version of the application using the same source code. This is a two-step process:
Defining the conditional compiler constant. This step is optional; conditional compiler constants that are not explicitly defined by the
#Const
directive, but are referenced in code, default to a value of Nothing.Evaluating the constant in the conditional compiler
#If...Then
statement block.
A conditional compiler constant can be assigned any string, numeric,
or logical value returned by an expression. However, the expression
itself can only consist of literals, operators other than
Is
, and another conditional compiler constant.
When the constant is evaluated, the code within the conditional
compiler #If...
Then
block is
compiled as part of the application only when the expression using
the conditional compiler constant evaluates to
True
.
Rules at a Glance
Conditional compiler constants are evaluated by the conditional compiler
#If... Then
statement block.You can use any arithmetic or ...
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