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JavaScript JavaScript Array Iteration Methods Combining Array Methods Working with Objects in Arrays

why using []

on minut 7:24 why he uses [user.name] ? i mean why the [] instead of plain user.name

2 Answers

Steven Parker
Steven Parker
228,025 Points

The entire expression is "usersObject[user.name]", so bracket notation is being used to access a specific property of the "usersObject". The value in user.name is the name of the property being created.

but if i want to acces property in object with bracket notation i need to add a string with it , am i right? like this const peoples ={ name: dani, age: 22 } peoples["name"]

Steven Parker
Steven Parker
228,025 Points

That's right, but the string can be a literal (as in your example) or it can come from a variable (as what user.name holds).

Jesus Mendoza
Jesus Mendoza
23,288 Points

When using variables to access elements inside an object you have to use [].

For example:

// Using plain property names
const obj = {
  name: 'Jesús'
console.log(obj.name) // logs Jesús

// Using variables
const propertyName = 'name';
const obj2 = {
  name: 'Jesús'
console.log(obj[propertyName]); // logs Jesús