How to create objects in javascript (steps)

JavaScript is a language that uses objects for programming, and creating objects correctly is one of the important parts of writing programs in JavaScript. In this article, we will learn the steps to create objects in JavaScript so that we can write efficient JavaScript programs.

Step 1: Determine the object type

First, we need to determine the type of object we want to create. In JavaScript, the object type can be a built-in type, such as an array (Array), date (Date) or regular expression (RegExp), or a custom class. If it is a custom class, we need to define the constructor of the class.

Step 2: Define the Object

Once we have decided on the object type, we need to define the object. In JavaScript, we can use object literals or create a constructor.

The syntax for creating objects using object literals is as follows:

var obj = {
  property1: value1,
  property2: value2,
  ...
};

The following is an example:

var person = {
  firstName: "John",
  lastName: "Doe",
  age: 30,
  eyeColor: "blue"
};

The syntax for creating objects using constructors is as follows:

function Person(firstName, lastName, age, eyeColor) {
  this.firstName = firstName;
  this.lastName = lastName;
  this.age = age;
  this.eyeColor = eyeColor;
}

Here is an example:

var person = new Person("John", "Doe", 30, "blue");

Step 3: Add properties and methods to the object

Once we have defined the object, we need to add properties and methods to the object. In JavaScript, we can add properties and methods to objects through dot syntax or square bracket syntax.

The syntax for adding properties and methods to an object using dot syntax is as follows:

objectName.propertyName = value;

objectName.methodName = function() {
  // code to be executed
};

The following is an example:

person.nationality = "English";

person.fullName = function() {
  return this.firstName + " " + this.lastName;
};

The syntax for adding properties and methods to an object using square bracket syntax As follows:

objectName["propertyName"] = value;

objectName["methodName"] = function() {
  // code to be executed
};

Here is an example:

person["nationality"] = "English";

person["fullName"] = function() {
  return this.firstName + " " + this.lastName;
};

Step 4: Using the object

Finally, we can use the object we created. We can access the properties and methods of the object and operate on them.

The syntax for accessing object properties and methods using dot syntax is as follows:

objectName.propertyName;

objectName.methodName();

The following is an example:

var x = person.age;

var y = person.fullName();

The syntax for accessing object properties and methods using square bracket syntax is as follows:

objectName["propertyName"];

objectName["methodName"]();

Here is an example:

var x = person["age"];

var y = person["fullName"]();

Conclusion

In this article, we learned the steps to create objects in JavaScript. We need to determine the object type, define the object, add properties and methods to the object, and use the object. Mastering these steps will enable you to write efficient JavaScript programs.

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