How Can Object Literal Keys Be Assigned Using Square Brackets in ES2015 Syntax?

Using Square Brackets in Object Literal Keys

It may be difficult to understand how keys can be assigned using square brackets within an object literal. Let's dive into the explanation behind this ES2015 syntax.

The code snippet you provided:

<code class="js">let a = "b"
let c = {[a]: "d"}</code>

uses the computed property name syntax, which is a shorthand for the traditional ES3/5 someObject[someKey] assignment. In other words, it expands to:

<code class="js">var a = "b"
var c = {}
c[a] = "d"</code>

This syntax allows you to dynamically generate property names based on variables or expressions, providing greater flexibility in object construction. When using this feature, ensure that the property name is enclosed in square brackets, as in [a] in the example.

The above is the detailed content of How Can Object Literal Keys Be Assigned Using Square Brackets in ES2015 Syntax?. For more information, please follow other related articles on the PHP Chinese website!