![]() You can have the same properties as the constructor function or add a new property to one. In all the tests I've run it is desperately slow compared to other methods, but might be useful when you need advanced capabilities and aren't going to be calling it hundreds of times. Each object created from the constructor function is unique. ![]() However this is complicated and cumbersome to use and doesn't appear to be well optimised in any current browser. There are also more formal methods for creating objects such as the Object.create() function. For the constructor method in classes, see its own reference page. Note: This is a property of JavaScript objects. Note that the value of this property is a reference to the function itself, not a string containing the function's name. In some cases the constructor can be pre-compiled, for example if it is defined in a javascript code module in a Firefox addon, and then it is a win-win. The constructor property returns a reference to the Object constructor function that created the instance object. Remember also that the initial creation of the constructor is an expensive operation, which may be more important if it is only to be used a few times. Creating an object with only value properties is another order of magnitude faster. Of course you are talking about a few micro-seconds (on a typical desktop) for creating an object with a small amount of embedded javascript vs less than a microsecond for calling a constructor, so in most cases it isn't important. If your object becomes non-trivial, for example including getters, setters, or full-blown methods, then a constructor (with the javascript in a prototype to be shared) is orders of magnitude faster than creating an object from scratch. Hey you just created a basic constructor function :lol: In our JavaScript fundamentals course, you should have learned the basics of using objects to store and retrieve data. You can always define a function if it is to be called from lots of different places. Examples of built-in constructors are Array, Date, and Object. The user simply needs to invoke them and viola, the work’s done. Built-in Constructors These are the readily available constructors that come bundled with the execution environment. Just creating a simple object literal from scratch each time is faster. There are two types of constructors in JavaScript 1. Using a constructor to create a trivial object with just value properties is counter-productive.
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