Xamarin
A Microsoft open-source app platform for building Android and iOS apps with .NET and C#.
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Exception of type 'System.Reflection.ReflectionTypeLoadException' was throw
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932
Reputation points
Hi
Visual Studio 2022 latest. Xamarin Forms.
I am trying to debug iOS project on a connected local iPhone device. The app installs and starts on device fine but then immediately closes. I am getting below in output in Visual Studio.
[0:] An error occurred: 'Exception of type 'System.Reflection.ReflectionTypeLoadException' was thrown.
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')
Could not resolve type with token 01000030 from typeref (expected class 'System.Security.Policy.EvidenceBase' in assembly 'System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a')'. Callstack: ' at (wrapper managed-to-native) System.Reflection.Assembly.GetTypes(System.Reflection.Assembly,bool)
at System.Reflection.Assembly.GetTypes () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/mcs/class/corlib/System.Reflection/Assembly.cs:243
at Xamarin.iOS.HotRestart.Application.ForceLoadingAssemblies (System.Type formsDelegate, System.String contentFolder) <0x124916620 + 0x000d2> in <98b03165b3364c75930281f33d5e323b>:0
at Xamarin.iOS.HotRestart.Application.Run (System.String[] args, System.Action`1[T] loadFrameworkAction, System.Action killApplicationAction) <0x124241868 + 0x00202> in <98b03165b3364c75930281f33d5e323b>:0 '
The app has been terminated.
How can I fix this pelase?
Thanks
Regards
{count} vote
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Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 32,386 Reputation points Microsoft Vendor2023-03-16T06:03:14.7666667+00:00 The error message points to
System.Reflection.Assembly.GetTypes (), which is in System.Runtime.dll.
What's the detailed iOS version of your device? The Xamarin.iOS version is 16.2, right? Could you debug the project on the simulator? -
-- -- 932 Reputation points
2023-03-16T15:23:19.3733333+00:00 Hi
iOS 16.3.1 (20D67). Xamarin iOS runtime version v4.0.30319.
I will try on simulator and come back.
Thanks
Regards
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Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 32,386 Reputation points Microsoft Vendor
2023-03-17T02:57:29.15+00:00 You could open VS, go to Help->About Visual Studio->Xamarin.iOS and Xamarin.Mac SDK, and see the detailed version. It might not contain 16.3.1 SDK. At meantime, I'm looking forward to seeing your feedback to check if it works on simulator. (You should pair to mac, and you can also try to test if you can deploy the app on your physical device in this way)
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-- -- 932 Reputation points
2023-03-18T10:42:00.4766667+00:00 Hi
Xamarin/mac related versions from VS Help->About
VisualStudio.Mac 1.0 Mac Extension for Visual Studio Xamarin 17.5.0.173 (d17-5@33e727c) Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android. Xamarin Designer 17.5.3.46 (remotes/origin/d17-5@e4dd80b2bb) Visual Studio extension to enable Xamarin Designer tools in Visual Studio. Xamarin Templates 17.5.41 (ba80d05) Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms. Xamarin.Android SDK 13.2.0.0 (d17-5/797e2e1) Xamarin.Android Reference Assemblies and MSBuild support. Mono: 6dd9def Java.Interop: xamarin/java.interop/main@149d70fe SQLite: xamarin/sqlite/3.40.0@fdc1e34 Xamarin.Android Tools: xamarin/xamarin-android-tools/main@9f02d77 Xamarin.iOS and Xamarin.Mac SDK 16.2.0.5 (7738c90c9) Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.Thanks
Regards
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Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 32,386 Reputation points Microsoft Vendor
2023-03-20T02:02:42.49+00:00 You are running on iOS 16.3.1 device but the Xamarin.iOS and Xamarin.Mac SDK version is 16.2.0.5.
You can try to pair to mac(keep using Xcode 14.2), then deploy the app on your device, and check if it works. -
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dolfinm 0 Reputation points2023-12-07T15:43:26.0766667+00:00 What is the resolution? I have the same issue using hot restart with it crashing on startup with the exact same exception. Both simulator and using Mac build host both fail to build with "Failed to resolve "System.Security.Policy.EvidenceBase" reference from System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
iPhone: iOS 16.3.1, Xamarin.iOS: 16.4.0.15, Xcode: 14.2
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