<html>
<head>
<title>Javascript Boolean</title>
</head>
<body>
<script type="text/javascript">
var YES = true;
var NO = false;
document.write(true +'<br />');//true
document.write(false);//false
</script>
</body>
</html>
true
false
<html>
<head>
<title>Javascript Booleans Value is True or False</title>
</head>
<body>
<h4>With a "Real" Value is True</h4>
<p id="true_bool"></p><br>
<h4>Without a "Real" is False</h4>
<p id="text_1"></p>
<p id="text_2"></p>
<p id="text_3"></p>
<p id="text_4"></p>
<p id="text_5"></p>
<p id="text_6"></p>
<p id="text_7"></p>
<script type="text/javascript">
var bool_1 = Boolean(54);
var bool_2 = Boolean(2.89);
var bool_3 = Boolean(-20);
var bool_4 = Boolean("JavaScript");
var bool_5 = Boolean('false');
var bool_6 = Boolean(4 + 5 + 2.88);
document.getElementById("true_bool").innerHTML =
"54 is : " + bool_1 + "<br>" +
"2.89 is : " + bool_2 + "<br>" +
"-20 is : " + bool_3 + "<br>" +
"This string is : " + bool_4 + "<br>" +
"String 'false' is : " + bool_5 + "<br>" +
"This Value is : " + bool_6;
var boolean_1 = new Boolean(0);
document.getElementById("text_1").innerHTML = boolean_1;
var boolean_2 = new Boolean(-0);
document.getElementById("text_2").innerHTML = boolean_2;
var boolean_3 = new Boolean("");
document.getElementById("text_3").innerHTML = boolean_3;
var boolean_4 = new Boolean(undefined);
document.getElementById("text_4").innerHTML = boolean_4;
var boolean_5 = new Boolean(null);
document.getElementById("text_5").innerHTML = boolean_5;
var boolean_6 = new Boolean(false);
document.getElementById("text_6").innerHTML = boolean_6;
var boolean_7 = new Boolean(NaN);
document.getElementById("text_7").innerHTML = boolean_7;
</script>
</body>
</html>
54 is : true
2.89 is : true
-20 is : true
This string is : true
String 'false' is : true
This Value is : true
false
false
false
false
false
false
false
Method | Description |
---|---|
toSource() | Returns the source of Boolean object as a string. |
toString() | Returns a string representing the specified boolean object. |
valueOf() | Returns the value of the Boolean object. |
<html>
<head>
<title>JavaScript boolean object : toSource() method</title>
</head>
<body>
<script type="text/javascript">
bool_inf = new Boolean(0);
document.write(bool_inf.toSource());
</script>
</body>
</html>
<html>
<head>
<title>JavaScript boolean object : toString() method</title>
</head>
<body>
<script type="text/javascript">
boolean_object = new Boolean(true);
if(boolean_object.toString() == "true")
alert("Both are equal....");
else
alert("Both are not equal");
</script>
</body>
</html>
<html>
<head>
<title>JavaScript boolean object : valueOf() method</title>
</head>
<body>
<script type="text/javascript">
bool_val = new Boolean(1);
document.write(bool_val.valueOf());
</script>
</body>
</html>
true