How do I get the object created during a constructor?

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Beginner question here. I am trying to use the class syntax in javascript to make an object. I want to add the object as whole to an arraylist when it is created. I would also like to loop through that array later. My question: how do I add the actual object created in the constructor. Example code:

class Example {
constructor(x,y,z) {

  this.x = x;
  this.y = y;
  this.z = z;


}

}

Ideally I want to, when an Example object is created, add it to an array of examples. Can I do this within the constructor function? Also, if I have an array of Examples: what is the correct syntax for for in looping through it.

  var examples = []
  for Example in examples

the constructor can simply add the object like this

var examples = []

class Example {

  constructor(x,y,z) {

    this.x = x;
    this.y = y;
    this.z = z;
    examples.push(this)

  }

}

Object.prototype.constructor, The constructor initializes the new object. The next three subsections discuss each of these actions in detail: Declaring a Variable to Refer to an Object  Various constructors are executed (always from the top of the hierarchy down to the most specific one, e.g., Object's constructor is executed first, then whatever other super-classes you have, then the actual class's). So the object already has memory for it, and it's being initialized by the constructors, not created.

Just push it into an array:

class Example {
  constructor() {
    Example.instances.push(this);
  }
}

Example.instances = [];

And you can iterate that like:

for(const instance of Example.instances) {
  //...
}

Creating Objects, If i call this constructor by Constructor c = new Constructor(4);. how can i use array in my code? Note: i want to specifically create the object inside  All objects (with the exception of objects created with Object.create(null)) will have a constructor property. Objects created without the explicit use of a constructor function (i.e. the object and array literals) will have a constructor property that points to the Fundamental Object constructor type for that object.

this is a little strange, but you should be able to add this line to the bottom of your constructor:

examples.push(this);

How do i access the object created inside constructor?, Initialization: The new operator is followed by a call to a constructor, which initializes the new object. Declaring a Variable to Refer to an Object. Previously, you  To create the new instance of the Person object, we first define a variable of type Person that will hold the object. In this example, we've called it dave. On the other side of the equals sign, we call the constructor method of our Person class and pass it four string values.

Creating Objects (The Java™ Tutorials > Learning the Java , object as an argument in the constructor rather than creating it yourself. This way, you can use the real one in your code, and use a mock in  A constructor in Java is a block of code similar to a method that’s called when an instance of an object is created. Here are the key differences between a constructor and a method: A constructor doesn’t have a return type. The name of the constructor must be the same as the name of the …

Initializing objects in Constructor, In Java, you create an object by creating an instance of a class or, in other Constructor methods are special methods provided by each Java class that are  To have two parts of the code reference the same "thing", you do not need to use a constructor, as it would create two things. Instead you use two different "names" or "references". References in Java are sort of like pointers in other languages, except that they are restricted in a number of interesting ways.

Constructors in Java - A complete study!!, Constructor in java: It is a block of code that initializes the newly created object. Types: Default and Parameterized constructor, java copy constructor. Second instruction is main thing. It actually invokes the constructor of super most class and in above case it is Object.java. And once the constructor of super most class (i.e. Object in this case) has been called, rest of the code does specific instructions written in code.

Comments
  • Construct the Example and then add it separately. It would be weird to add it to an array from within the constructor without good reason. What is your reason behind wanting to?
  • yes, much better to store the list as a property on the class rather than as a variable in the outer scope (as done in the currently accepted answer). A WeakSet would be even better, though, since the current list would prevent garbage collection.
  • @alnitak not really, one can't iterate weaksets.
  • Good point, although the point remains that that array of instances will prevent garbage collection.