WebView

Question

目前我正在设置请求消息的User-Agent如下：

var rm = new HttpRequestMessage(HttpMethod.Post, new Uri("http://example.com"));       
rm.Headers.Add("User-Agent", "UserAgentString");
webView.NavigateWithHttpRequestMessage(rm);

一切正常。

但是，当我导航到另一个页面时，例如通过单击站点上的 link，User-Agent 将重置为默认值 WebView。

是否有任何方法可以永久设置用户代理或在每个请求时更改它？

谢谢，乔治

Answer 1

NavigationStarting 在 webview 导航到新内容之前发生。您可以取消该操作获取 args.Uri 并使用 HttpRequestMessage 导航。还有FrameNavigationStarting。

WebView wb = new WebView();
wb.NavigationStarting += A_NavigationStarting;

private void A_NavigationStarting(WebView sender, WebViewNavigationStartingEventArgs args)
{
    //this will throw `WhosebugException` so you have to add a condition here
    if(handled)
    {
        args.Cancel = true;
        var rm = new HttpRequestMessage(HttpMethod.Post, args.Uri);

        rm.Headers.Add("User-Agent", "UserAgentString");
        sender.NavigateWithHttpRequestMessage(rm);
    }
}

Answer 2

我能够相当可靠地工作的唯一方法是使用 NavigationStarting 事件取消页面加载并获取当前 url，然后使用自定义事件触发新的使用正确的 UA 加载页面。

public sealed partial class MainPage : Page
{
    private bool headerSent;
    private Uri uri;

    private delegate void NavigateHandler(object sender, EventArgs e);
    private event NavigateHandler OnNavigate;

    public MainPage()
    {
        this.InitializeComponent();

        this.OnNavigate += new NavigateHandler(Navigate);
        this.headerSent = false;
        this.webview.Navigate(new Uri("https://netflix.com"));
    }

    private void Navigate(object sender, EventArgs e)
    {
        this.headerSent = true;
        var rm = new HttpRequestMessage(HttpMethod.Post, this.uri);

        rm.Headers.Add("User-Agent", @"Mozilla/5.0 (Windows NT 10.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12.10136");
        this.webview.NavigateWithHttpRequestMessage(rm);
    }

    private void webview_NavigationStarting(WebView sender, WebViewNavigationStartingEventArgs args)
    {
        if (!headerSent)
        {
            args.Cancel = true;
            this.uri = args.Uri;
            OnNavigate(this, new EventArgs());
        }
        else if (headerSent)
        {
            headerSent = false;
        }
    }
}

不漂亮，但它似乎有效。

Answer 3

我找到了 this trick by Matt Dot。这将永久更改 user-agent 字符串。任何 WebView 请求，无论是手动请求还是通过 HTML 中的 link-click，都会将您的值作为 User-Agent header.

发送

如果 link 死了，这里是来源。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace UA
{
    public static class UserAgent
    {
        const int URLMON_OPTION_USERAGENT = 0x10000001;

        [DllImport("urlmon.dll", CharSet = CharSet.Ansi)]
        private static extern int UrlMkSetSessionOption(int dwOption, string pBuffer, int dwBufferLength, int dwReserved);

        [DllImport("urlmon.dll", CharSet = CharSet.Ansi)]
        private static extern int UrlMkGetSessionOption(int dwOption, StringBuilder pBuffer, int dwBufferLength, ref int pdwBufferLength, int dwReserved);

        public static string GetUserAgent()
        {
            int capacity = 255;
            var buf = new StringBuilder(capacity);
            int length = 0;

            UrlMkGetSessionOption(URLMON_OPTION_USERAGENT, buf, capacity, ref length, 0);

            return buf.ToString();
        }

        public static void SetUserAgent(string agent)
        {
            var hr = UrlMkSetSessionOption(URLMON_OPTION_USERAGENT, agent, agent.Length, 0);
            var ex = Marshal.GetExceptionForHR(hr);
            if(null != ex)
            {
                throw ex;
            }
        }

        public static void AppendUserAgent(string suffix)
        {
            SetUserAgent(GetUserAgent() + suffix);
        }
    }
}

您可以在应用中的任何位置更改此值，但如果您希望永久设置它，请使用 App.xaml.cs 构造函数：

public App()
{
    UA.UserAgent.SetUserAgent("Firefox ;)");

    // ...
}

WebView - 在每个请求上定义 User-Agent

WebView - Define User-Agent on every request

c#

httprequest

win-universal-app

windows-10-universal