Electron 提供了一个实时构建桌面应用的纯 JavaScript 环境。Electron 可以获取到你定义在 package.json 中 main 文件内容，然后执行它。通过这个文件（通常我们称之为 main.js），可以创建一个应用窗口，这个应用窗口包含一个渲染好的 web 界面，还可以和系统原生的 GUI 交互。
具体来说，就是当你启动了一个 Electron 应用，就有一个主进程（main process ）被创建了。这条进程将负责创建出应用的 GUI（也就是应用的窗口），并处理用户与这个 GUI 之间的交互。
但直接启动 main.js 是无法显示应用窗口的，在 main.js 中通过调用BrowserWindow模块才能将使用应用窗口。然后每个浏览器窗口将执行它们各自的渲染器进程（ renderer process ）。渲染器进程将会处理一个真正的 web 页面（HTML + CSS + JavaScript），将页面渲染到窗口中。鉴于 Electron 使用的是基于 Chrominum 的浏览器内核，你就不太需要考虑兼容的问题。
const {app, BrowserWindow} = require('electron')
const path = require('path')
const url = require('url')
// Keep a global reference of the window object, if you don't, the window will
// be closed automatically when the JavaScript object is garbage collected.
let win
function createWindow() {
// Create the browser window.
win = new BrowserWindow({ width: 800, height: 600, autoHideMenuBar: true })
// and load the index.html of the app.
win.loadURL(url.format({
pathname: path.join(__dirname, 'index.html'),
protocol: 'file:',
slashes: true
}))
// Open the DevTools.
win.webContents.openDevTools()
// Emitted when the window is closed.
win.on('closed', () => {
// Dereference the window object, usually you would store windows
// in an array if your app supports multi windows, this is the time
// when you should delete the corresponding element.
win = null
})
}
// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.on('ready', createWindow)
// Quit when all windows are closed.
app.on('window-all-closed', () => {
// On macOS it is common for applications and their menu bar
// to stay active until the user quits explicitly with Cmd + Q
if (process.platform !== 'darwin') {
app.quit()
}
})
app.on('activate', () => {
// On macOS it's common to re-create a window in the app when the
// dock icon is clicked and there are no other windows open.
if (win === null) {
createWindow()
}
})
// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and require them here.