Name
CBool Function
Syntax
CBool(expression
)
expression
Use: Required
Data Type: String or Numeric
Any numeric expression or a string representation of a numeric value.
Return Value
expression
converted to a type of
Boolean (True
or False
).
Description
Casts expression
as aa Boolean
type. Expressions that evaluate to 0 are converted to False
(0), and expressions that evaluate
to nonzero values are converted to True
(-1).
Rules at a Glance
If the expression to be converted is a string, the string must
act as a number. Therefore, CBool("ONE")
results in a type mismatch
error, yet CBool("1")
converts to
True
.
Programming Tips and Gotchas
You can check the validity of the expression prior to using the CBool function by using the IsNumeric function.
When you convert an expression to a Boolean, an expression that evaluates to 0 is converted to
False
(0), and any nonzero number is converted toTrue
(-1). Therefore, a BooleanFalse
can be converted back to its original value (i.e., 0), but the original value of theTrue
expression can’t be restored unless it was originally -1.
See Also
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