.NET MAUI 8.0 iOS调试报错：Dynamic code generation is not supported on this platform

升级.NET MAUI 8.0应用到.NET 8.0.7运行环境后，iOS平台抛出Dynamic code generation is not supported on this platform.异常，具体堆栈信息如下：

Exception has occurred: CLR/System.PlatformNotSupportedException
An unhandled exception of type 'System.PlatformNotSupportedException' occurred in System.Private.CoreLib.dll: 'Dynamic code generation is not supported on this platform.'
   at System.Reflection.Emit.AssemblyBuilder.ThrowDynamicCodeNotSupported()
   at System.Reflection.Emit.AssemblyBuilder.EnsureDynamicCodeSupported()
   at System.Reflection.Emit.DynamicMethod.Init(String name, MethodAttributes attributes, CallingConventions callingConvention, Type returnType, Type[] signature, Type owner, Module m, Boolean skipVisibility, Boolean transparentMethod)
   at System.Reflection.Emit.DynamicMethod..ctor(String name, Type returnType, Type[] parameterTypes, Type owner, Boolean skipVisibility)
   at DryIoc.FastExpressionCompiler.LightExpression.ExpressionCompiler.TryCompileBoundToFirstClosureParam(Type delegateType, Expression bodyExpr, IParameterProvider paramExprs, Type[] closurePlusParamTypes, Type returnType, CompilerFlags flags)
   at DryIoc.FactoryDelegateCompiler.CompileToFactoryDelegate(Expression expression, Boolean preferInterpretation)
   at DryIoc.Container.System.IServiceProvider.GetService(Type serviceType)
   at Microsoft.Maui.MauiContext.WrappedServiceProvider.GetService(Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetService[T](IServiceProvider provider)
   at Microsoft.Maui.Controls.DispatcherExtensions.FindDispatcher(BindableObject bindableObject)
   at Microsoft.VisualStudio.DesignTools.MauiTap.MauiHelpers.GetDispatcher(BindableObject bindableObject)
   at Microsoft.VisualStudio.DesignTools.MauiTap.MauiHelpers.GetDispatcher(IWindow window)
   at Microsoft.VisualStudio.DesignTools.MauiTap.ElementSelectionManager.RegisterWindow(IWindow window)
   at Microsoft.VisualStudio.DesignTools.MauiTap.ElementSelectionManager.Initialize()
   at Microsoft.Maui.Dispatching.Dispatcher.<>c__DisplayClass9_0.<DispatchImplementation>b__0()
   at CoreFoundation.DispatchQueue.static_dispatcher_to_managed(IntPtr context)
   at UIKit.UIApplication.xamarin_UIApplicationMain(Int32 argc, IntPtr argv, IntPtr principalClassName, IntPtr delegateClassName, IntPtr& gchandle)
   at UIKit.UIApplication.UIApplicationMain(Int32 argc, String[] argv, IntPtr principalClassName, IntPtr delegateClassName)
   at UIKit.UIApplication.Main(String[] args, Type principalClass, Type delegateClass)

解决方案 #

• 禁用DryIoc的表达式编译
  异常根源是DryIoc尝试使用依赖动态代码生成的表达式编译器，而iOS平台限制了该功能。可以在配置DryIoc容器时强制使用解释模式，避免触发动态代码生成：

  var container = new Container(rules => rules.With(FactoryMethod.Interpret));
  

  或者使用“编译失败则回退解释”的模式：

  var container = new Container(rules => rules.With(FactoryMethod.CompileIfFails | FactoryMethod.Interpret));
  

• 排查Visual Studio调试工具冲突
  堆栈中出现Microsoft.VisualStudio.DesignTools.MauiTap相关代码，说明可能是VS的MAUI调试工具触发了问题：

  • 将Visual Studio更新到与.NET 8.0.7兼容的最新版本
  • 暂时关闭XAML热重载或设计时预览功能，验证是否能绕过异常
  • 尝试以非调试模式运行应用，确认是否仅在调试场景出现问题

• 检查iOS项目配置
  确认iOS项目的「iOS Build」设置中：

  • 未勾选「Enable dynamic code generation」（iOS默认禁用，误开启会引发冲突）
  • 若启用了AOT编译，确保代码中没有依赖动态代码生成的逻辑，AOT环境下该功能本身不被支持

内容的提问来源于stack exchange，提问作者Anand