Constructor
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A constructor belongs to a particular class {{glossary("object")}} that is instantiated. The constructor initializes this object and can provide access to its private information. The concept of a constructor can be applied to most {{glossary("OOP","object-oriented programming")}} languages. Essentially, a constructor in {{glossary("JavaScript")}} is usually declared at the instance of a {{glossary("class")}} .
Syntax
// This is a generic default constructor class Default
function Default() {}
// This is an overloaded constructor class Overloaded
// with parameter arguments
function Overloaded(arg1, arg2, /* …, */ argN) {}
To call the constructor of the class in JavaScript, use a new operator to assign a new {{glossary("object reference")}} to a {{glossary("variable")}} .
function Default() {}
// A new reference of a Default object assigned to a
// local variable defaultReference
const defaultReference = new Default();