Learn JavaScript Object Methods: Manipulation and Iteration
JavaScript objects are an integral part of modern web development, allowing developers to easily organize and manage data. It consists of key-value pairs and is the heart of many programming problems. In this article, we will explore important JavaScript object methods that allow you to efficiently manipulate and iterate over objects.
Create an object
Before we dive into the methods, let's look at how to create objects in JavaScript. There are two general ways to create objects:
- Object Literal Syntax:
const person = {
Name: "John Doe"
age: 30
Profession: "Web Developer"
};
- Constructor Functions:
function Person(name, age, profession) {
this.name = name;
this.age = age;
this.work = work;
}
const person = new Person("John Doe", 30, "Web Developer");
Manipulation Methods
1. Object.keys(), Object.values(), Object.entry()
This method allows you to extract keys, values, and individual key-value pairs from an object.
const person = {
Name: "John Doe"
age: 30
Profession: "Web Developer"
};
const key = Object.keys(man); // ["name", "age", "profession"]
const value = Object.values(person); // ["John Doe", 30, "Web Developer"]
const entry = Object.entry(person); // [["Name", "John Doe"], ["age", 30], ["Deaf", "Web Developer"]]
2. Object.assign()
The Object.assign() method is used to copy enumerated property values from one or more source objects to the target object.
const target = {};
const source = {a: 1, b: 2};
Object.assign(target, source);
console.log(target); // {a: 1, b: 2}
3. Object.defineProperty()
This method allows you to set or change properties on the object by directly controlling the property properties.
const person = {};
object.defineProperty(person, "name", {
Value: "John Doe"
can be written: false, // Can't be changed
unnumbered: true, // Shown in circles
configurable: false // Can not be deleted or changed
});
Iteration method
1. for inloop
A "for in" loop iterates over the enumerated properties of the object.
const person = {
Name: "John Doe"
age: 30
Profession: "Web Developer"
};
for (private key) {
console.log(`${key}: ${person[key]}`);
}
2. Object.case (). forEach()
This method combines the Object.keys () method and the forEach () method for a short iteration.
const person = {
Name: "John Doe"
age: 30
Profession: "Web Developer"
};
Object.keys(person).forEach(key => {
console.log(`${key}: ${person[key]}`);
});
3. Object.entry (). forEach()
Similar to the previous method, "Object.entry().ForEach()" iterates through key-value pairs.
const person = {
Name: "John Doe"
age: 30
Profession: "Web Developer"
};
Object.entry(person).forEach(([key, value]) => {
console.log(`${key}:${value}`);
});
The results
JavaScript object methods play an important role in object manipulation and iteration. By using methods like "Object.keys ()", "Object.values ()", "Object.entry ()", "Object.assign ()" and more, you can work efficiently with objects in your program. Whether you create, modify, or modify objects, this method provides the tools you need to effectively manage your data in the dynamic world of web development.