ADOBE® FLEX® 3: PROGRAMMING ACTIONSCRIPT™ 3.0

ADOBE FLEX 3

Developer Guide

58

Casting to Boolean from a String value returns false if the string is either null or an empty string (""). Otherwise,

it returns

true.

var str1:String; // Uninitialized string is null.

trace(Boolean(str1));// false

var str2:String = "";// empty string

trace(Boolean(str2));// false

var str3:String = " "; // white space only

trace(Boolean(str3));// true

Casting to Boolean from an instance of the Object class returns false if the instance is null; otherwise, it returns

true:

var myObj:Object;// Uninitialized object is null.

trace(Boolean(myObj)); // false

myObj = new Object();// instantiate

trace(Boolean(myObj)); // true

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