全国网站建设人员数量,中国建设银行陕西分行官方网站,wordpress动画,微信商城公众号背景前些天遇到一个需求#xff0c;在没有第三方源码的情况下#xff0c;刷新一个第三方UI#xff0c;并且拦截到其ajax请求的返回结果。当结果为AVALIABLE的时候#xff0c;停止刷新并语音提示#xff0c;否则继续刷新。分析这个需求#xff0c;发现需要控制一个刷新循环… 背景前些天遇到一个需求在没有第三方源码的情况下刷新一个第三方UI并且拦截到其ajax请求的返回结果。当结果为AVALIABLE的时候停止刷新并语音提示否则继续刷新。分析这个需求发现需要控制一个刷新循环的暂停与开始因此网上搜到了通过ManualResetEvent实现线程的暂停与恢复。ManualResetEvent介绍ManualResetEvent是一个通过信号机制实现线程间状态同步的类。常用的方法有以下三个WaitOne阻止当前线程直到收到信号Reset将事件状态设置为非终止状态导致线程阻止Set将事件状态设置为终止状态从而允许继续执行一个或多个等待线程实现设计1.通过CefSharp的谷歌浏览器插件请求第三方网站 2.具体交互逻辑如下默认开启一个线程并通过WaitOne挂起等待手动开始自动刷新的指令手动通过Set方法发送开始工作信号执行完面操作后通过Reset将线程再次挂起并等待Ajax结果判断Ajax结果如果不等于AVALIABLE则再次恢复线程public Form1()
{InitializeComponent();var setting new CefSettings();setting.Locale zh-CN;setting.UserAgent Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36;// 避免页面加载不出来, 建议加上这句Cef.Initialize(setting);workerThread new Thread(new ThreadStart(BeginListenWorkerAsync));workerThread.IsBackground true;workerThread.Start();this.停止自动监听ToolStripMenuItem.Enabled false;
}private async void BeginListenWorkerAsync()
{while (true){_eventBeginListenWorkList.WaitOne(); //1.默认挂起线程等待信号chromiumWebBrowser1.GetBrowser().MainFrame.ExecuteJavaScriptAsync(document.evaluate(//*[idroot]/div[1]/div[2]/div/div[2]/div[1]/div[1]/div/div[1]/button, document).iterateNext().click());Thread.Sleep(1000);chromiumWebBrowser1.GetBrowser().MainFrame.ExecuteJavaScriptAsync(document.evaluate(//*[idroot]/div[1]/div[2]/div/div[1]/div/div/div/div[2]/div[6]/div/button, document).iterateNext().click());_eventBeginListenWorkList.Reset(); //3.页面执行完相应操作则再次挂起线程等待ajax请求结果再判断是否恢复线程}
}private void 停止自动监听ToolStripMenuItem_Click(object sender, EventArgs e)
{this.开始自动监听ToolStripMenuItem.Enabled true;this.停止自动监听ToolStripMenuItem.Enabled false;_eventBeginListenWorkList.Reset();StartListen false;
}private void 开始自动监听ToolStripMenuItem_Click(object sender, EventArgs e)
{this.开始自动监听ToolStripMenuItem.Enabled false;this.停止自动监听ToolStripMenuItem.Enabled true;_eventBeginListenWorkList.Set(); // 2.手动通过Set发送信号恢复线程让其工作StartListen true;
} 3.现在我们需要定义RequestHandler来指定ResourceHandler拦截ajax请求private void Form1_Load(object sender, EventArgs e)
{chromiumWebBrowser1.RequestHandler new MyRequestHandler(this);chromiumWebBrowser1.Load(https://www.xxxxxxxx.com/);
}MyRequestHandler中需要指定自定义ResourceHandlerpublic class MyRequestHandler : RequestHandler
{Form1 _form;public MyRequestHandler(Form1 form){_form form;}public static string AuthorizationValue;protected override bool OnBeforeBrowse(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, bool userGesture,bool isRedirect){// 先调用基类的实现断点调试return base.OnBeforeBrowse(chromiumWebBrowser, browser, frame, request, userGesture, isRedirect);}protected override IResourceRequestHandler GetResourceRequestHandler(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame,IRequest request, bool isNavigation, bool isDownload, string requestInitiator, ref bool disableDefaultHandling){Console.WriteLine(request.Url);if (request.Url.StartsWith(https://www.xxxxxxxxxxxxxxxx/api) request.Headers.AllKeys.Contains(Authorization)){AuthorizationValue request.Headers[Authorization];}return new MyResourceRequestHandler(_form);}
}4.最后ResourceRequestHandler拦截到ajax请求之后如果结果不是AVALIABLE则通过StartListenFunc再次恢复线程public class MyResourceRequestHandler : ResourceRequestHandler
{Form1 _form;public MyResourceRequestHandler(Form1 form){_form form;}private Dictionaryulong, MemoryStreamResponseFilter responseDictionary new Dictionaryulong, MemoryStreamResponseFilter();protected override IResponseFilter GetResourceResponseFilter(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IResponse response){var dataFilter new MemoryStreamResponseFilter();responseDictionary.Add(request.Identifier, dataFilter);return dataFilter;}protected override void OnResourceLoadComplete(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IResponse response, UrlRequestStatus status, long receivedContentLength){MemoryStreamResponseFilter filter;if (responseDictionary.TryGetValue(request.Identifier, out filter)){var data filter.Data;if (request.Url.StartsWith(https://xxxxxxxxxxxxxxxxxxxx/oneapi)){var available false;string s System.Text.Encoding.UTF8.GetString(data, 0, data.Length);Console.WriteLine(s);if (!string.IsNullOrEmpty(s)){var responseData JsonConvert.DeserializeObjectScheduleResponse(s);if (responseData ! null responseData.productPreviews ! null){foreach (var item in responseData.productPreviews){if (item.schedule ! null item.schedule.status ! null item.schedule.status.name AVAILABLE){available true;Mp3Player.Play();Action act delegate () { _form.StopListen(); };_form.Invoke(act);break;}}}}if (!available Form1.StartListen){Form1.StartListenFunc();}}filter.Dispose();}}
} 而StartListenFunc则是通过Set方法再次恢复了线程对ui的重复查询public static void StartListenFunc()
{_eventBeginListenWorkList.Set();StartListen true;
}ManualResetEvent官方介绍如下https://docs.microsoft.com/zh-cn/dotnet/api/system.threading.manualresetevent?viewnetframework-1.1
