Returns an expression converted to the Boolean data type.
CBool ( expr )
expr
Any numeric expression, or the string expressions True and False.
CBool returns an expression that has been converted to Boolean.
CBool(EMPTY) returns False.
If expr is a numeric expression, CBool returns True or False, depending on the value of the numeric expression: 0 becomes False, and any other value becomes True.
If expr lies outside the acceptable range for the Boolean data type, the function raises an error.