1>

 private lazy var webV : UIWebView = {

        let v = UIWebView(frame: self.view.bounds)

        let url = URL(string: "https://www.baidu.com/")

        v.delegate = self

        if let url = url {

            let  urlRequest = URLRequest(url: url)

            v.loadRequest(urlRequest)

        }

        return v

    }()

2>

    override func viewDidLoad() {

        super.viewDidLoad()

        view.addSubview(webV)

    }

3>

extension ViewController:UIWebViewDelegate{

}

1>

private lazy var wkWebV: WKWebView = {

        let config = WKWebViewConfiguration()

        // 设置偏好设置

        config.preferences = WKPreferences()

        //        // 默认为0

        //        config.preferences.minimumFontSize = 10

        // 默认认为YES

        config.preferences.javaScriptEnabled = true

        // 在iOS上默认为NO，表示不能自动通过窗口打开

        config.preferences.javaScriptCanOpenWindowsAutomatically = false

        // web内容处理池，由于没有属性可以设置，也没有方法可以调用，不用手动创建

        config.processPool = WKProcessPool()

        // 通过JS与webview内容交互

        config.userContentController = WKUserContentController()

        // 注入JS对象名称AppModel，当JS通过AppModel来调用时，

        // 我们可以在WKScriptMessageHandler代理中接收到

//        config.userContentController.add(self, name: "AppModel")

        let url = URL(string: "https://www.baidu.com/")

        let web = WKWebView(frame: view.bounds, configuration: config)

        web.navigationDelegate = self

        web.uiDelegate = self

        if let url = url {

            let  urlRequest = URLRequest(url: url)

            web.load(urlRequest)

        }

        return web

    }()

2>

view.addSubview(wkWebV)

3.

extension ViewController:WKNavigationDelegate,WKUIDelegate,WKScriptMessageHandler{

    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {

    }

}