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Unit 5: Scripting Language
And all the following lines of code create Boolean objects with an initial value of true: Notes
var myBoolean=new Boolean(true);
var myBoolean=new Boolean(“true”);
var myBoolean=new Boolean(“false”);
var myBoolean=new Boolean(“Richard”);
Table 5.5: Boolean Object Methods
Method Description
toString() Converts a Boolean value to a string, and returns the result
valueOf() Returns the primitive value of a Boolean object
Example: Check if a Boolean object is true or false.
<html>
<body>
<script type=”text/javascript”>
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 is boolean “+ b1 +”<br />”);
document.write(“1 is boolean “+ b2 +”<br/>”);
document.write(“An empty string is boolean “+ b3 + “<br />”);
document.write(“null is boolean “+ b4+ “<br />”);
document.write(“NaN is boolean “+ b5 +”<br />”);
document.write(“The string ‘false’ is boolean “+ b6 +”<br />”);
</script>
</body>
</html>
Output
0 is boolean false
1 is boolean true
An empty string is boolean false
null is boolean false
NaN is boolean false
The string ‘false’ is boolean true
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