Home  >  Article  >  Web Front-end  >  What are the objects in js

What are the objects in js

下次还敢
下次还敢Original
2024-05-10 04:54:171168browse

In JavaScript, an object is a collection of key-value pairs, where the key is used to identify the value. Features include: scalability, ordered keys, and the ability to dynamically modify properties. Use curly braces to create an object, use the dot operator or square brackets to access properties, use the assignment operator to modify properties, and use the delete operator to delete properties. Objects are reference types and can be nested and have other types, such as arrays, dates, etc.

What are the objects in js

Objects in JavaScript

In JavaScript, an object is a data type that stores key values A collection of pairs, where the key identifies the value.

Characteristics of the object:

  • Key: A unique string or symbol used to identify the value.
  • Value: Can be any other JavaScript data type (string, number, boolean, array, object, etc.).
  • Extensibility: Objects can dynamically add or delete key-value pairs.
  • Ordering: Keys are stored in the order they are added, but values ​​are not.

Create objects:

You can create objects using the following syntax:

<code class="javascript">const myObject = {
  name: "John",
  age: 30,
  isMale: true,
};</code>

Access object properties:

You can use the dot operator (.) or square brackets ([]) to access object properties:

<code class="javascript">console.log(myObject.name); // John
console.log(myObject["age"]); // 30</code>

Modify object properties:

You can use assignment Operator (=) to modify object properties:

<code class="javascript">myObject.name = "Jane";</code>

Delete object properties:

You can use the delete operator to delete object properties:

<code class="javascript">delete myObject.isMale;</code>

Additional information:

  • Objects are reference types, which means that modifications to the object affect the original object.
  • Objects can be nested, which means they can contain other objects.
  • Other object types are also provided in JavaScript, such as arrays, dates, errors, etc.

The above is the detailed content of What are the objects in js. For more information, please follow other related articles on the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn