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JS Object Methods
Method |
Description |
Example |
|---|---|---|
Modifying Object Properties |
let person = {
name: "John",
};
person.age = 30 // {name:"John",age:30}
delete person.name // {age:30}
|
|
Get all keys in the object. |
let person = {
name: "John",
age : 30
};
Object.keys(person) // ["name", "age"]
|
|
Get all values in the object. |
let person = {
name: "John",
age : 30
};
Object.values(person) // ["John", 30]
|
|
Get key-value pairs as an array. |
let person = {
name: "John",
age : 30
};
Object.entries(person) // [["name", "John"], ["age", 31]]
|
|
Copy properties from one object to another. |
let person = {
name: "John",
age : 30
};
const additionalInfo = { profession: "Engineer" };
const updatedPerson = Object.assign(person, additionalInfo);
// {name: "John",age : 30,profession: "Engineer"};
|
|
Prevents modifications (add, delete, or update) |
let person = {
name: "John",
};
Object.freeze(person);
person.age = 30 // error will through
|
|
Prevents adding or deleting, but allows updating existing properties. |
let person = {
name: "John",
};
Object.seal(person);
person.name = "Doe" // {name : "Doe"}
person.age = 30 // error will through
delete person.name // error will through
|
Add and delete Object:
Modifying Object Properties
Example
let person = {
name: "John",
};
person.age = 30 // {name:"John",age:30}
delete person.name // {age:30}
Object.keys():
Get all keys in the object.
Example
let person = {
name: "John",
age : 30
};
Object.keys(person) // ["name", "age"]
Object.values():
Get all values in the object.
Example
let person = {
name: "John",
age : 30
};
Object.values(person) // ["John", 30]
Object.entries():
Get key-value pairs as an array.
Example
let person = {
name: "John",
age : 30
};
Object.entries(person) // [["name", "John"], ["age", 31]]
Object.assign():
Copy properties from one object to another.
Example
let person = {
name: "John",
age : 30
};
const additionalInfo = { profession: "Engineer" };
const updatedPerson = Object.assign(person, additionalInfo);
// {name: "John",age : 30,profession: "Engineer"};
Object.freeze():
Prevents modifications (add, delete, or update)
Example
let person = {
name: "John",
};
Object.freeze(person);
person.age = 30 // error will through
Object.seal():
Prevents adding or deleting, but allows updating existing properties.
Example
let person = {
name: "John",
};
Object.seal(person);
person.name = "Doe" // {name : "Doe"}
person.age = 30 // error will through
delete person.name // error will through