如何访问其中范围外的变量？

Question

这是我的代码，我正在尝试访问 page.evaulate 范围内的 anum 和 articleHTML。它说 anum 和 articleHTML 未定义

const num = context.params.event.content.split(' ').slice(1).join(' ')
let an = parseInt(num)
let anum = an - 1
let articleHTML = an + 1



let website = 'https://newkrunktimes.github.io/'

let browser = await puppeteer.launch();
let page = await browser.newPage()

await page.goto(website, {waitUntil: 'networkidle2'})



let data = await page.evaluate(() => {  

  articleTitle = document.getElementsByClassName("post-title h4 font-weight-bold")[anum].innerText
  author = document.getElementsByClassName("post-supertitle")[anum].innerText
  aImage = document.getElementsByClassName("img-fluid")[anum].currentSrc
  aDesc = document.getElementsByClassName("post-content font-weight-light")[anum].innerText
  artLink = document.querySelector(`a[class="ytlink"][target="_blank"][href="articles/article${articleHTML}.html"]`).href
  
  return {
    articleTitle,
    author,
    aImage,
    aDesc,
    artLink
    }
  
})

Answer 1

这背后的原因是浏览器上下文中 page.evaluate() 运行中的任何内容都不是定义 anum 和 articleHTML 的上下文（node.js 上下文).

我想你会在这里找到答案：

如何访问其中范围外的变量？

How do I access variables outside a scope inside it?

puppeteer