运行时用户代理更改

Question

我正在尝试在我的应用中添加移动、桌面版网站功能。但问题是User Agent 只会在 webView 加载之前立即更改。在我的应用程序中，我为Mobile 添加按钮一个，为Desktop 版本站点添加第二个按钮。 UIWebView 选择 User Agent 刚开始。谁能告诉我有没有办法在运行时更改 User Agent。谢谢

 var defaultUserAgent = String()
    @IBOutlet weak var webView: UIWebView!

    @IBOutlet weak var activityIndicator: UIActivityIndicatorView!

    override func viewDidLoad() {
        super.viewDidLoad()

        let url = NSURL(string: "https://www.youtube.com")
        let request = NSURLRequest(URL: url!)
        activityIndicator.hidesWhenStopped = true
        activityIndicator.startAnimating()
        webView.loadRequest(request)
    }

    @IBAction func mobile(sender: AnyObject) {
        NSUserDefaults.standardUserDefaults().registerDefaults(["UserAgent": defaultUserAgent])
        print(defaultUserAgent)

        let url = NSURL(string: "https://www.youtube.com")
        let request = NSURLRequest(URL: url!)
        activityIndicator.hidesWhenStopped = true
        activityIndicator.startAnimating()
        webView.loadRequest(request)

    }

    @IBAction func desktop(sender: AnyObject) {

        NSUserDefaults.standardUserDefaults().registerDefaults(["UserAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/48.0.2564.109 Safari/537.36"])

        let url = NSURL(string: "https://www.youtube.com")
        let request = NSURLRequest(URL: url!)
        activityIndicator.hidesWhenStopped = true
        activityIndicator.startAnimating()
        webView.loadRequest(request)

    }

    func webViewDidFinishLoad(webView: UIWebView) {
        activityIndicator.stopAnimating()
        print(webView.stringByEvaluatingJavaScriptFromString("navigator.userAgent"))
        defaultUserAgent = webView.stringByEvaluatingJavaScriptFromString("navigator.userAgent")!
    }

Answer 1

我建议你使用 WkWebView 而不是 UIWebView，因为它相对更强大l

iOS 9 的 WkWebView 有直接的 API

 if #available(iOS 9, *) {
            webViewObj.customUserAgent = "customUserAgentValue"
 }