javascript puppeteer：我如何等待 ajax 请求并处理结果
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puppeteer : how can i wait for ajax request and process the result
提问by hretic
so i open a website , waith for all redirects to be done capture captcha image and send it vie nodejs to a user an recive the typed captcha
所以我打开一个网站，等待所有重定向完成捕获验证码图像并将其通过 vie nodejs 发送给用户并接收输入的验证码
const browser = await puppeteer.launch({headless: false});
const page = await browser.newPage();
await page.goto('http://localhost/p1.php' );
await page.waitForNavigation();
const captcha_image = await page.$eval('#security', e => e.getAttribute('src'));
io.emit('send_captcha_to_client' , {text : captcha_image });
var captcha = await captchaPromise;
after i reciv the typed value of capthca i put it in the field and click the login button
在我收到 capthca 的输入值后，我将其放入该字段并单击登录按钮
await page.$eval('#W_CAPTCHA', (el , _captcha) => el.value = _captcha.W_CAPTCHA , captcha );
await page.click('#login-btn');
now after clicking the button a ajax request will be send to the server lets say http://example.com/login.php... and if the captcha is right , i'll get redirected to my dashboard but if the ajax call returns lets say {status:er}
现在点击按钮后，ajax 请求将被发送到服务器让我们说http://example.com/login.php...如果验证码是正确的，我将被重定向到我的仪表板但如果 ajax 调用返回让我们说 {status:er}
and there is <span id="alert"></span>in the page it'll add .Errorclass to it and put the error text in there ... how can i intercept the ajax call and check if the login was successful or not ?
并且 <span id="alert"></span>在页面中它会.Error向它添加类并将错误文本放在那里......我如何拦截ajax调用并检查登录是否成功？
i can cehck the result of ajax call or wait and check the document for div.Errorbut not sure how can i do any of them .. here is my failed attempt !
我可以检查 ajax 调用的结果或等待并检查文档，div.Error但不确定我该怎么做..这是我失败的尝试！
await page.waitForNavigation();
page.waitForSelector('.Error');
const error = await page.$eval('.Error', e => e.value );
console.log(error);
browser.close();
回答by Aankhen
You can wait on both simultaneously and handle whichever occurs first:
您可以同时等待并处理先发生的情况：
await Promise.race([
page.waitForNavigation({ waitUntil: "networkidle0" }),
page.waitForSelector(".Error")
]);
if (await page.$(".Error")) {
// there was an error
} else {
// the page changed
}
