Boolean objects are used to convert non-Boolean values into Boolean values (true or false).
Check Boolean value
Checks whether a boolean object is true or false.
Source code example:
<!DOCTYPE html>
<html>
<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 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>
Test results:
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
Create Boolean object
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 -0 null "" false undefined NaN
Then the value of the object is false. Otherwise, its value is true (even when the argument is the string "false")!
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