Boolean (Boolean - JavaScript)
Creates a Boolean object.
Defined in
Boolean (Standard - JavaScript)Syntax
Boolean()
Boolean(value:boolean)
Parameters | Description |
---|---|
value |
A value that converts to true or false. Defaults to false. |
Usage
The following values convert to true:- The literal
true
, a boolean variable whose value is true, or an expression that evaluates to true. - A string that is not empty.
- A number other than 0 or -0.
The following values convert to false:
- The literal
false
, a boolean variable whose value is false, or an expression that evaluates to false. - An empty string.
- The number 0 or -0.
- The literal
undefined
,null
, orNaN
, or a variable or expression with that value.
Examples
(1) This computed label displaystrue
or false
.var F = new Boolean();
var T = new Boolean(true);
T.toString() + " or " + F.toString()
(2) This computed
label also displays
true or false
.var F = new Boolean(0);
var T = new Boolean(1);
T.toString() + " or " + F.toString()
(3) This computed
label displays
true
if the value of the global variable width
is
greater than the value of the global variable length
.
The global variables are bound to numeric fields.var b = new Boolean(
sessionScope.width > sessionScope.height);
b.toString()