cefsharp如何拦截request,详细代码

首先，需要使用 CefSharp 的 RequestHandler 接口来拦截请求。具体的步骤如下：

1. 创建一个类，实现 IRequestHandler 接口，并实现其中的方法。

class CustomRequestHandler : IRequestHandler
{
    public bool OnBeforeBrowse(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, bool isRedirect)
    {
        // TODO: Implement this method
        return false;
    }

    public bool OnBeforeResourceLoad(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
    {
        // TODO: Implement this method
        return false;
    }

    public void OnResourceRedirect(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response, ref string newUrl)
    {
        // TODO: Implement this method
    }

    public bool GetAuthCredentials(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, bool isProxy, string host, int port, string realm, string scheme, IAuthCallback callback)
    {
        // TODO: Implement this method
        return false;
    }

    public bool OnSelectClientCertificate(IWebBrowser chromiumWebBrowser, IBrowser browser, bool isProxy, string host, int port, X509Certificate2Collection certificates, ISelectClientCertificateCallback callback)
    {
        // TODO: Implement this method
        return false;
    }

    public void OnPluginCrashed(IWebBrowser chromiumWebBrowser, IBrowser browser, string pluginPath)
    {
        // TODO: Implement this method
    }

    public bool OnBeforePluginLoad(IWebBrowser chromiumWebBrowser, IBrowser browser, string url, string policyUrl, WebPluginInfo info)
    {
        // TODO: Implement this method
        return false;
    }

    public CefReturnValue OnBeforeResourceLoad(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
    {
        // TODO: Implement this method
        return CefReturnValue.Continue;
    }

    public bool OnCertificateError(IWebBrowser chromiumWebBrowser, IBrowser browser, CefErrorCode errorCode, string requestUrl, ISslInfo sslInfo, IRequestCallback callback)
    {
        // TODO: Implement this method
        return false;
    }

    public void OnRenderProcessTerminated(IWebBrowser chromiumWebBrowser, IBrowser browser, CefTerminationStatus status)
    {
        // TODO: Implement this method
    }

    public void OnRenderViewReady(IWebBrowser chromiumWebBrowser, IBrowser browser)
    {
        // TODO: Implement this method
    }

    public bool OnResourceResponse(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
    {
        // TODO: Implement this method
        return false;
    }

    public void OnResourceLoadComplete(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response, UrlRequestStatus status, long receivedContentLength)
    {
        // TODO: Implement this method
    }
}

2. 在主窗体中，创建一个 ChromiumWebBrowser 控件，并设置 RequestHandler。

var browser = new ChromiumWebBrowser("http://www.example.com");
browser.RequestHandler = new CustomRequestHandler();

3. 在 CustomRequestHandler 中实现 OnBeforeResourceLoad 方法，拦截请求。

public bool OnBeforeResourceLoad(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
{
    if (request.Url.ToLower().Contains("example.com"))
    {
        // 拦截请求，根据需要修改 request 对象
        request.Headers["User-Agent"] = "My User Agent";
        request.Method = "POST";
        request.PostData = new CefSharp.PostData();
        request.PostData.AddElement(new CefSharp.PostDataElement("param1=value1&param2=value2"));

        return true;
    }

    return false;
}

4. 运行程序，访问指定的网站，可以看到拦截到的请求已被修改。

需要注意的是，以上代码仅用于演示如何拦截请求，并可能不适用于所有场景。具体实现需要根据实际情况进行调整。