Boolean( ) Global Function

ActionScript for Flash MX: The Definitive Guide, 2nd Edition
By Colin Moock
Chapter 18.  ActionScript Language Reference
Boolean( ) Global Function Flash 5

convert a value to the boolean datatype
Boolean(value)

Arguments

value

An expression containing the value to be converted to a Boolean.

Returns

The result of converting value to a primitive Boolean (either true or false).

Description

The Boolean( ) global function converts its argument to a primitive Boolean value and returns that converted value. The results of converting various datatypes to a primitive Boolean are described in Table 3-3 in Chapter 3. It's normally not necessary to use the Boolean( ) function; ActionScript automatically converts values to the boolean type when appropriate.

Usage

Be sure not to confuse the global Boolean( ) function with the Boolean class constructor. The Boolean( ) function converts its argument to the boolean datatype, whereas the Boolean class constructor creates a new Boolean object. Note that in ECMA-262, all nonempty strings convert to true. In Flash, only strings that can be converted to a valid nonzero number convert to true. Therefore, even the string "true" converts to the Boolean false.

Example

var x = 1; if (Boolean(x)) {   trace("x is true"); }

See Also

The Boolean class; "Datatype Conversion," in Chapter 3

     



    ActionScript for Flash MX. The Definitive Guide
    ActionScript for Flash MX: The Definitive Guide, Second Edition
    ISBN: 059600396X
    EAN: 2147483647
    Year: 2002
    Pages: 780
    Authors: Colin Moock

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