javascript - Electron webContents执行JavaScript : Cannot execute script on second on loadURL

Question

我正在测试 Electron，特别是使用executeJavaScript。我的项目使用 POST 请求登录网站，然后执行一些工作并使用同一 session 加载第二个 URL。在第二个 URL 中，我需要执行 JS，但我不确定我做错了什么。

在这个例子中，我创建了一个简化版本，模拟访问两个 URL 并在第二个 URL 上执行 JS。对这里发生的事情有什么想法吗？

const {app, BrowserWindow} = require('electron');

let win;

function createWindow() {

  win = new BrowserWindow({width: 1000, height: 600})
  win.openDevTools();

  // First URL
  win.loadURL('https://www.google.com')

  // Once dom-ready
  win.webContents.once('dom-ready', () => {

    // THIS WORKS!!!
    win.webContents.executeJavaScript(`
      console.log("This loads no problem!");
    `)

    // Second URL
    win.loadURL('https://github.com/electron/electron');

    // Once did-navigate seems to function fine
    win.webContents.once('did-navigate', () => {

      // THIS WORKS!!! So did-navigate is working!
      console.log("Main view logs this no problem....");

      // NOT WORKING!!! Why?
      win.webContents.executeJavaScript(`

        console.log("I canot see this nor the affects of the code below...");

        const form = document.querySelectorAll('form.js-site-search-form')[0];

        const input = form.querySelectorAll('input.header-search-input')[0]

        input.value = 'docs';

        form.submit();

      `)

    })
  })
}

app.on('ready', createWindow );

app.on('window-all-closed', () => {
  if (process.platform !== 'darwin') {
    app.quit();
  }
});

Answer 1

这是因为您尝试在 dom-ready 事件之前运行 Javascript。

尝试在此事件完成后执行您的 JavaScript，如下所示

const { app, BrowserWindow } = require('electron');

let win;

function createWindow() {

    win = new BrowserWindow({ width: 1000, height: 600 })
    win.openDevTools();

    // First URL
    win.loadURL('https://www.google.com')

    // Once dom-ready
    win.webContents.once('dom-ready', () => {

        // THIS WORKS!!!
        win.webContents.executeJavaScript(`
      console.log("This loads no problem!");
    `)

        // Second URL
        win.loadURL('https://github.com/electron/electron');

        // Once did-navigate seems to function fine
        win.webContents.once('did-navigate', () => {

            // THIS WORKS!!! So did-navigate is working!
            console.log("Main view logs this no problem....");
            win.webContents.once('dom-ready', () => {
                // NOT WORKING!!! Why?
                win.webContents.executeJavaScript(`

        console.log("I canot see this nor the affects of the code below...");

        const form = document.querySelectorAll('input.js-site-search-form')[0];

        const input = form.querySelectorAll('input.header-search-input')[0]

        input.value = 'docs';

        form.submit();

      `)

            })
        });
    })
    }

    app.on('ready', createWindow);

    app.on('window-all-closed', () => {
        if (process.platform !== 'darwin') {
            app.quit();
        }
    });