JavaScript Boolean object

JavaScript Boolean (Boolean) Object

TBoolean (Boolean) object is used to convert non-Boolean values to Boolean values (true or false).

Create a Boolean object

The Boolean object represents two values: "true" or "false"

The following code defines a Boolean object named myBoolean:

var myBoolean=new Boolean();

If the Boolean object has no initial value or its value is:

0-0null""falseundefinedNaN

Then the object's The value is false. Otherwise, its value is true (even when the argument is the string "false")!

Continuing Learning

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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>php中文网(php.cn)</title>
</head>
<body>
<script>
var b1=new Boolean(0);
var b2=new Boolean(1);
var b3=new Boolean("");
var b4=new Boolean(null);
var b5=new Boolean(NaN);
var b6=new Boolean("false");
document.write("0 为布尔值 "+ b1 +"<br>");
document.write("1 为布尔值 "+ b2 +"<br>");
document.write("空字符串是布尔值 "+ b3 + "<br>");
document.write("null 是布尔值 "+ b4+ "<br>");
document.write("NaN 是布尔值 "+ b5 +"<br>");
document.write("字符串'false' 是布尔值"+ b6 +"<br>");
</script>
</body>
</html>
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