UWP App RequestRestartAsync在System.Private.Corelib中引发异常

Question

My computer is on Windows 10 build 16299, which is the minimum required version for the UWP restart functionality in CoreApplication.RequestRestartAsync(...) . However, after I make the call to restart, with arguments of string.Empty , the App does close and a few seconds later an Exception is thrown from System.Private.CoreLib.dll :

Exception occurred: System.Exception: Exception from HRESULT: 0x80040900
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()

I am able to get this information from a Try/Catch block and am running the app from Visual Studio 2017 in debug mode. Before I attempted to catch it, a dialog would appear indicating to debug in another instance of Visual Studio. When the other instance loaded, this was not allowed because it said a debugger was already attached.

Additionally, I tried to catch it by enabling "Common Language Runtime Exceptions", but it did not catch this Exception.

Why is this happening? When I use run this on another Windows 10 machine, the restart works fine. Can I debug or get more information about the Exception in System.Private.CoreLib ?

Answer 1

This error will not happen to affect your app's real experience when you install your app and run it without connecting the Visual studio to debug. Visual Studio prevents Windows from suspending an app that is attached to the debugger. This is to allow the user to view the Visual Studio debug UI while the app is running. When you debug this code with Visual Studio, you can see the App status is still Running in your device Task Manager => Details tab after you called this method, so the app can not restart, since prior to Windows 10, version 1803, only one instance of a UWP app could be running at a time. More details about multi-instance UWP, please see Create a multi-instance Universal Windows App .

But in my test on the device OS version 1803 OS build 17134 and Visual studio version 15.7, it will disconnect the Visual Studio debugger automatically after you call CoreApplication.RequestRestartAsync(string.Empty) code.