如何在Xamarin.Forms iOS应用程序中为UiWebView设置用户代理

Question

I am currently setting the user agent of the UIWebView within my HybridWebViewRenderer in my iOS project in my Xamarin.Forms app.

It does work but only at first, subsequent web requests do not have the UserAgent.

I am setting the UserAgent as follows in OnElementChanged in HybridWebViewRenderer and my understanding is that this will be called once when the WebView is created.

   public class HybridWebViewRenderer : ViewRenderer<HybridWebView, UIWebView>, IWKScriptMessageHandler
{
    protected override void OnElementChanged(ElementChangedEventArgs<HybridWebView> e)
    {
        base.OnElementChanged(e);

        if (Control == null)
        {
            UIWebView agentWebView = new UIWebView();
            var userAgent = agentWebView.EvaluateJavascript("navigator.userAgent");
            userAgent += "MyApp";
            NSDictionary dictionary = NSDictionary.FromObjectAndKey(NSObject.FromObject(userAgent), NSObject.FromObject("UserAgent"));
            NSUserDefaults.StandardUserDefaults.RegisterDefaults(dictionary);
            agentWebView.ShouldStartLoad += HandleStartLoad;
            base.SetNativeControl(agentWebView);
            agentWebView.LoadRequest(new NSUrlRequest(new NSUrl(e.NewElement.Uri.ToString())));

        }
    }

Answer 1

我使用完全相同的代码，但我在构造函数而不是OnElementChanged事件中执行此操作。