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JavaScript Tutorial: Booleans

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JavaScript Boolean variables take one of two values, true or false. They are instantiated by a statement such as:

 

var b = true;

 

You can usually use the global Boolean() function to identify whether an expression is true or false, although it is simpler just to use operators that return Boolean outputs, e.g. Boolean(2 > 1), (2 > 1) or even 2 > 1 all return true. It is worth noting that the global Boolean() function returns an object and this can in some circumstances behave counterintuitively relative to the primitive Boolean values of true and false.

 

Boolean objects support the following properties and methods:

 

Properties:

 

Property	Description	More
constructor	Returns object’s constructor function	Here
length	Returns the length of a Boolean object	Here
prototype	Allows author to add properties and methods to an object	Here

 

Methods:

 

Method	Description	More
toString()	Converts boolean value to a string	Here
valueOf()	Returns the primitive value of the object	Here

 

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