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Logical NOT Operator (!) (Windows Scripting - JScript)

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Performs logical negation on an expression.

Syntax

result = !expression

Arguments

  • result
    Any variable.

  • expression
    Any expression.

Remarks

The following table illustrates how result is determined.

If expression is

Then result is

True

False

False

True

All unary operators, such as the ! operator, evaluate expressions as follows:

  • If applied to undefined or null expressions, a run-time error is raised.

  • Objects are converted to strings.

  • Strings are converted to numbers if possible. If not, a run-time error is raised.

  • Boolean values are treated as numbers (0 if false, 1 if true).

The operator is applied to the resulting number.

For the ! operator, if expression is nonzero, result is zero. If expression is zero, result is 1.

Requirements

Version 1

See Also

Bitwise NOT Operator (~) (Windows Scripting - JScript)
Operator Precedence (Windows Scripting - JScript)
Operator Summary (Windows Scripting - JScript)