Question

为什么使用此代码，它只对console.log做东西两次？

class Something extends React.Component {
    componentDidMount() {
        this.doStuff();
    }

    doStuff() {
        console.log('do stuff')
        setTimeout(this.doStuff, 3000);
    }

    render() {
        return null
    }
}

Answer 1

第一次超时后，I am sharing my solution, this would not write any logs to any file but you can collect all sort of messages such as Errors, Warnings, Logs, Info, Debug , CSS, XHR as well as Requests(traffic) 1. We are going to create Firefox profile so that we can enable option of "Persist Logs" on Firefox (you can try it to enable on your default browser and see if it launches with "Persist Logs" without creating firefox profile ) 2. we need to modify the Firefox initialize code where this line will do magic : options.AddArgument("--jsconsole"); so complete Selenium Firefox code would be, this will open Browser Console everytime you execute your automation : else if (browser.Equals(Constant.Firefox)) { var profileManager = new FirefoxProfileManager(); FirefoxProfile profile = profileManager.GetProfile("ConsoleLogs"); FirefoxDriverService service = FirefoxDriverService.CreateDefaultService(DrivePath); service.FirefoxBinaryPath = DrivePath; profile.SetPreference("security.sandbox.content.level", 5); profile.SetPreference("dom.webnotifications.enabled", false); profile.AcceptUntrustedCertificates = true; FirefoxOptions options = new FirefoxOptions(); options.AddArgument("--jsconsole"); options.AcceptInsecureCertificates = true; options.Profile = profile; options.SetPreference("browser.popups.showPopupBlocker", false); driver = new FirefoxDriver(service.FirefoxBinaryPath, options, TimeSpan.FromSeconds(100)); driver.Manage().Timeouts().ImplicitWait = TimeSpan.FromSeconds(10); } 3. Now you can write your logic since you have traffic/ logging window open so don't go to next execution if test fails. That way Browser Console will keep your errors messages and help you to troubleshoot further Browser : Firefox v 61 How can you launch Browser Console for firefox: 1. open firefox (and give any URL ) 2. Press Ctrl+Shift+J (or Cmd+Shift+J on a Mac) Link : https://developer.mozilla.org/en-US/docs/Tools/Browser_Console将是this对象，并且在window对象上没有doStuff方法，因此它将不再运行。 / p>

您可以例如将window函数转换为箭头函数，它将具有封闭词法上下文的doStuff值。

this

class Something extends React.Component {
    componentDidMount() {
        this.doStuff();
    }

    doStuff = () => {
        console.log('do stuff');
        setTimeout(this.doStuff, 1000);
    }

    render() {
        return null;
    }
}

ReactDOM.render(<Something />, document.getElementById('root'));

在反应中使用setTimeout进行轮询

1 个答案: