Windows Form中CefSharp多浏览器窗口创建报错解决问询
在Windows Form项目中使用CefSharp实现网页浏览功能时,每次打开新的SlaytBrowser窗口,都会在窗口加载事件中执行Cef.Initialize操作,抛出**“CEF can only be initialized once per process”**异常。即使关闭已打开的浏览器窗口,也无法创建新窗口。需求是无论是否关闭已有窗口,都能无错误创建新的CefSharp浏览器窗口。

报错详情
以下是JIT调试的替代错误对话框,详情请查看本消息末尾。
************** 异常文本 **************
System.Exception: CEF每个进程只能初始化一次。这是底层CEF/Chromium框架的限制。你可以通过RequestContext.SetPreference在运行时修改许多(并非全部)设置。使用Cef.IsInitialized来避免此异常。如果意外出现此错误,可能是你在创建ChromiumWebBrowser实例后调用了Cef.Initialize,它必须在第一个实例创建之前调用。
在 CefSharp.Core.Cef.Initialize(CefSettingsBase cefSettings, Boolean performDependencyCheck, IApp cefApp) 位置 C:\projects\cefsharp\CefSharp.Core.Runtime\Cef.h:行 260
在 CefSharp.Core.Cef.Initialize(CefSettingsBase cefSettings, Boolean performDependencyCheck, IBrowserProcessHandler browserProcessHandler) 位置 C:\projects\cefsharp\CefSharp.Core.Runtime\Cef.h:行 242
在 CefSharp.Cef.Initialize(CefSettingsBase settings, Boolean performDependencyCheck, IBrowserProcessHandler browserProcessHandler) 位置 C:\projects\cefsharp\CefSharp.Core\Cef.cs:行 146
在 _404_Masaüstü_Uygulaması.SlaytBrowser.SlaytBrowser_Load(Object sender, EventArgs e) 位置 C:\Users\Harun\source\repos\Uc_Haftada_C_Sharp\404 Masaüstü Uygulaması\404 Masaüstü Uygulaması\SlaytBrowser.cs:行 31
在 System.Windows.Forms.Form.OnLoad(EventArgs e)
在 System.Windows.Forms.Form.OnCreateControl()
在 System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
在 System.Windows.Forms.Control.CreateControl()
在 System.Windows.Forms.Control.WmShowWindow(Message& m)
在 System.Windows.Forms.Control.WndProc(Message& m)
在 System.Windows.Forms.ScrollableControl.WndProc(Message& m)
在 System.Windows.Forms.Form.WmShowWindow(Message& m)
在 System.Windows.Forms.Form.WndProc(Message& m)
在 System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
在 System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
在 System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)************** 加载的程序集 **************
mscorlib
程序集版本: 4.0.0.0
Win32版本: 4.8.4515.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/mscorlib.dll404 Masaüstü Uygulaması
程序集版本: 1.0.0.0
Win32版本: 1.0.0.0
CodeBase: file:///C:/Users/Harun/source/repos/Uc_Haftada_C_Sharp/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/bin/x86/Debug/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1.exeSystem.Windows.Forms
程序集版本: 4.0.0.0
Win32版本: 4.8.4550.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dllSystem
程序集版本: 4.0.0.0
Win32版本: 4.8.4536.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dllSystem.Drawing
程序集版本: 4.0.0.0
Win32版本: 4.8.4390.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dllSystem.Configuration
程序集版本: 4.0.0.0
Win32版本: 4.8.4190.0 built by: NET48REL1LAST_B
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dllSystem.Core
程序集版本: 4.0.0.0
Win32版本: 4.8.4566.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dllSystem.Xml
程序集版本: 4.0.0.0
Win32版本: 4.8.4084.0 built by: NET48REL1
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dllmscorlib.resources
程序集版本: 4.0.0.0
Win32版本: 4.8.4084.0 built by: NET48REL1
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/mscorlib.resources/v4.0_4.0.0.0_tr_b77a5c561934e089/mscorlib.resources.dllAccessibility
程序集版本: 4.0.0.0
Win32版本: 4.8.4084.0 built by: NET48REL1
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Accessibility/v4.0_4.0.0.0__b03f5f7f11d50a3a/Accessibility.dllCefSharp.WinForms
程序集版本: 106.0.290.0
Win32版本: 106.0.290.0
CodeBase: file:///C:/Users/Harun/source/repos/Uc_Haftada_C_Sharp/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/bin/x86/Debug/CefSharp.WinForms.DLLCefSharp.Core
程序集版本: 106.0.290.0
Win32版本: 106.0.290.0
CodeBase: file:///C:/Users/Harun/source/repos/Uc_Haftada_C_Sharp/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/bin/x86/Debug/CefSharp.Core.DLLCefSharp
程序集版本: 106.0.290.0
Win32版本: 106.0.290.0
CodeBase: file:///C:/Users/Harun/source/repos/Uc_Haftada_C_Sharp/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/bin/x86/Debug/CefSharp.DLLCefSharp.Core.Runtime
程序集版本: 106.0.290.0
Win32版本: 106.0.290
CodeBase: file:///C:/Users/Harun/source/repos/Uc_Haftada_C_Sharp/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/404%20Masa%C3%BCst%C3%BC%20Uygulamas%C4%B1/bin/x86/Debug/CefSharp.Core.Runtime.DLLSystem.Windows.Forms.resources
程序集版本: 4.0.0.0
Win32版本: 4.8.4084.0 built by: NET48REL1
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms.resources/v4.0_4.0.0.0_tr_b77a5c561934e089/System.Windows.Forms.resources.dll************** JIT调试 **************
要启用JIT调试,需在应用程序或计算机的machine.config文件的system.windows.forms节中设置jitDebugging值为true。同时应用程序需在调试模式下编译。例如:
启用JIT调试后,未处理的异常将被发送到计算机上注册的JIT调试器,而不是在此对话框中处理。
现有代码
创建新SlaytBrowser窗口代码
private void ders6btn_Click(object sender, EventArgs e) { SlaytBrowser slayt_acici = new SlaytBrowser(); slayt_acici.url = "https://www.google.com"; slayt_acici.Show(); }
SlaytBrowser窗口代码
private void SlaytBrowser_Load(object sender, EventArgs e) { CefSettings settings = new CefSettings(); settings.CefCommandLineArgs.Add("disable-gpu", "1"); Cef.Initialize(settings, performDependencyCheck: true, browserProcessHandler: null); chrome = new ChromiumWebBrowser(url); this.panel1.Controls.Add(chrome); chrome.Dock = DockStyle.Fill; chrome.AddressChanged += Chrome_AddressChanged; } private void Chrome_AddressChanged(object sender, AddressChangedEventArgs e) { this.Invoke(new MethodInvoker(() => { url = e.Address; })); } private void button1_Click(object sender, EventArgs e) { chrome.Load(url); }
解决方案
核心原因
CEF框架限制每个进程只能初始化一次,当前在每个窗口的Load事件中重复调用Cef.Initialize,导致第二次打开窗口时触发异常。
修复步骤
将CEF初始化移到应用程序启动时
在项目的Program.cs中,在启动主窗体之前完成CEF的初始化,确保整个进程只执行一次:static class Program { [STAThread] static void Main() { // 初始化CEF CefSettings settings = new CefSettings(); settings.CefCommandLineArgs.Add("disable-gpu", "1"); if (!Cef.IsInitialized) { Cef.Initialize(settings, performDependencyCheck: true, browserProcessHandler: null); } Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new MainForm()); // 你的主窗体 // 应用退出时关闭CEF Application.ApplicationExit += (s, e) => { if (Cef.IsInitialized) { Cef.Shutdown(); } }; } }修改SlaytBrowser窗口代码,移除重复初始化
去掉SlaytBrowser_Load中的Cef.Initialize调用,直接创建ChromiumWebBrowser实例:private void SlaytBrowser_Load(object sender, EventArgs e) { chrome = new ChromiumWebBrowser(url); this.panel1.Controls.Add(chrome); chrome.Dock = DockStyle.Fill; chrome.AddressChanged += Chrome_AddressChanged; }确保窗口关闭时正确清理资源
在SlaytBrowser的FormClosing事件中释放浏览器资源,避免内存泄漏:private void SlaytBrowser_FormClosing(object sender, FormClosingEventArgs e) { chrome?.Dispose(); }
说明
Cef.IsInitialized用于检查CEF是否已初始化,避免重复调用Initialize- 应用退出时调用
Cef.Shutdown,确保CEF资源被正确释放 - 每个新窗口只需要创建
ChromiumWebBrowser实例,无需再次初始化CEF
内容的提问来源于stack exchange,提问作者tanjavaner

