JavaScriptKit

Overview

JavaScriptKit provides a seamless way to interact with JavaScript from Swift code when compiled to WebAssembly.

Quick Start

Check out the Quick Start: Hello World tutorial for a step-by-step guide to getting started.

Key Features

• Access JavaScript objects and functions

• Create closures that can be called from JavaScript

• Convert between Swift and JavaScript data types

• Use JavaScript promises with Swift’s async/await

• Work with multi-threading

Example

import JavaScriptKit

// Access global JavaScript objects
let document = JSObject.global.document

// Create and manipulate DOM elements
var div = document.createElement("div")
div.innerText = "Hello from Swift!"
_ = document.body.appendChild(div)

// Handle events with Swift closures
var button = document.createElement("button")
button.innerText = "Click me"
button.onclick = .object(JSClosure { _ in
    JSObject.global.alert!("Button clicked!")
    return .undefined
})
_ = document.body.appendChild(button)

Check out the examples for more detailed usage.

Tutorials

• Quick Start: Hello World

  This tutorial walks you through creating a simple web application using JavaScriptKit. You’ll learn how to set up a Swift package, add JavaScriptKit as a dependency, write code to manipulate the DOM, and build and run your web application.

  Read More

Core Types

• enum JSValue

  JSValue represents a value in JavaScript.

• class JSObject

  JSObject represents an object in JavaScript and supports dynamic member lookup. Any member access like object.foo will dynamically request the JavaScript and Swift runtime bridge library for a member with the specified name in this object.

• class JSClosure

  JSClosure represents a JavaScript function the body of which is written in Swift. This type can be passed as a callback handler to JavaScript functions.