如何在不丢失C＃中的堆栈跟踪的情况下抛出InnerException？

﹏ヽ暗。殇╰゛Y 2022-11-28 10:52 98阅读 0赞

本文翻译自：[How to rethrow InnerException without losing stack trace in C\#?][How to rethrow InnerException without losing stack trace in C]

*I am calling, through reflection, a method which may cause an exception.* **我正在通过反射调用可能导致异常的方法。** *How can I pass the exception to my caller without the wrapper reflection puts around it?* **在没有包装反射的情况下，如何将异常传递给调用者？**  
*I am rethrowing the InnerException, but this destroys the stack trace.* **我抛出了InnerException，但是这破坏了堆栈跟踪。**  
*Example code:* **示例代码：**

public void test1()
    {
        // Throw an exception for testing purposes
        throw new ArgumentException("test1");
    }
    
    void test2()
    {
        try
        {
            MethodInfo mi = typeof(Program).GetMethod("test1");
            mi.Invoke(this, null);
        }
        catch (TargetInvocationException tiex)
        {
            // Throw the new exception
            throw tiex.InnerException;
        }
    }

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### \#1楼 ###

参考：[https://stackoom.com/question/eVx/如何在不丢失C-中的堆栈跟踪的情况下抛出InnerException][https_stackoom.com_question_eVx_C-_InnerException]

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### \#2楼 ###

public static class ExceptionHelper
    {
        private static Action<Exception> _preserveInternalException;
    
        static ExceptionHelper()
        {
            MethodInfo preserveStackTrace = typeof( Exception ).GetMethod( "InternalPreserveStackTrace", BindingFlags.Instance | BindingFlags.NonPublic );
            _preserveInternalException = (Action<Exception>)Delegate.CreateDelegate( typeof( Action<Exception> ), preserveStackTrace );            
        }
    
        public static void PreserveStackTrace( this Exception ex )
        {
            _preserveInternalException( ex );
        }
    }

*Call the extension method on your exception before you throw it, it will preserve the original stack trace.* **在抛出异常之前对扩展方法进行调用，它将保留原始堆栈跟踪。**

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### \#3楼 ###

*In **.NET 4.5** there is now the [`ExceptionDispatchInfo`][ExceptionDispatchInfo] class.* **在.NET 4.5中 ，现在有了[`ExceptionDispatchInfo`][ExceptionDispatchInfo]类。**

*This lets you capture an exception and re-throw it without changing the stack-trace:* **这使您可以捕获异常并重新引发它，而无需更改堆栈跟踪：**

try
    {
        task.Wait();
    }
    catch(AggregateException ex)
    {
        ExceptionDispatchInfo.Capture(ex.InnerException).Throw();
    }

*This works on any exception, not just `AggregateException` .* **这适用于任何异常，而不仅仅是`AggregateException` 。**

*It was introduced due to the `await` C\# language feature, which unwraps the inner exceptions from `AggregateException` instances in order to make the asynchronous language features more like the synchronous language features.* **它是由于`await` C＃语言功能而引入的，该功能从`AggregateException`实例解包了内部异常，以使异步语言功能更像同步语言功能。**

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### \#4楼 ###

*Guys, you are cool.. I'm gonna be a necromancer soon.* **伙计们，你很酷..我很快就会成为一个死灵法师。**

public void test1()
        {
            // Throw an exception for testing purposes
            throw new ArgumentException("test1");
        }
    
        void test2()
        {
                MethodInfo mi = typeof(Program).GetMethod("test1");
                ((Action)Delegate.CreateDelegate(typeof(Action), mi))();
    
        }

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### \#5楼 ###

*It **is** possible to preserve the stack trace before rethrowing without reflection:* **这是可能的，而不反射重新抛出之前保存堆栈跟踪：**

static void PreserveStackTrace (Exception e)
    {
        var ctx = new StreamingContext  (StreamingContextStates.CrossAppDomain) ;
        var mgr = new ObjectManager     (null, ctx) ;
        var si  = new SerializationInfo (e.GetType (), new FormatterConverter ()) ;
    
        e.GetObjectData    (si, ctx)  ;
        mgr.RegisterObject (e, 1, si) ; // prepare for SetObjectData
        mgr.DoFixups       ()         ; // ObjectManager calls SetObjectData
    
        // voila, e is unmodified save for _remoteStackTraceString
    }

*This wastes a lot of cycles compared to calling `InternalPreserveStackTrace` via cached delegate, but has the advantage of relying only on public functionality.* **与通过缓存的委托调用`InternalPreserveStackTrace`相比，这浪费了很多周期，但是具有仅依赖于公共功能的优点。** *Here are a couple of common usage patterns for stack-trace preserving functions:* **以下是堆栈跟踪保留功能的两种常见用法模式：**

// usage (A): cross-thread invoke, messaging, custom task schedulers etc.
    catch (Exception e)
    {
        PreserveStackTrace (e) ;
    
        // store exception to be re-thrown later,
        // possibly in a different thread
        operationResult.Exception = e ;
    }
    
    // usage (B): after calling MethodInfo.Invoke() and the like
    catch (TargetInvocationException tiex)
    {
        PreserveStackTrace (tiex.InnerException) ;
    
        // unwrap TargetInvocationException, so that typed catch clauses 
        // in library/3rd-party code can work correctly;
        // new stack trace is appended to existing one
        throw tiex.InnerException ;
    }

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### \#6楼 ###

*Nobody has explained the difference between `ExceptionDispatchInfo.Capture( ex ).Throw()` and a plain `throw` , so here it is.* **没有人能解释`ExceptionDispatchInfo.Capture( ex ).Throw()`和普通`throw`之间的区别，所以就在这里。**

*The complete way to rethrow a caught exception is to use `ExceptionDispatchInfo.Capture( ex ).Throw()` (only available from .Net 4.5).* **抛出异常的完整方法是使用`ExceptionDispatchInfo.Capture( ex ).Throw()` （仅适用于.Net 4.5）。**

*Below there are the cases necessary to test this:* **以下是一些必要的测试案例：**

*1.* **1。**

void CallingMethod()
    {
        //try
        {
            throw new Exception( "TEST" );
        }
        //catch
        {
        //    throw;
        }
    }

*2.* **2。**

void CallingMethod()
    {
        try
        {
            throw new Exception( "TEST" );
        }
        catch( Exception ex )
        {
            ExceptionDispatchInfo.Capture( ex ).Throw();
            throw; // So the compiler doesn't complain about methods which don't either return or throw.
        }
    }

*3.* **3。**

void CallingMethod()
    {
        try
        {
            throw new Exception( "TEST" );
        }
        catch
        {
            throw;
        }
    }

*4.* **4。**

void CallingMethod()
    {
        try
        {
            throw new Exception( "TEST" );
        }
        catch( Exception ex )
        {
            throw new Exception( "RETHROW", ex );
        }
    }

*Case 1 and case 2 will give you a stack trace where the source code line number for the `CallingMethod` method is the line number of the `throw new Exception( "TEST" )` line.* **情况1和情况2将为您提供堆栈跟踪，其中`CallingMethod`方法的源代码行号是`throw new Exception( "TEST" )`行的行号。**

*However, case 3 will give you a stack trace where the source code line number for the `CallingMethod` method is the line number of the `throw` call.* **但是，情况3将为您提供堆栈跟踪，其中`CallingMethod`方法的源代码行号是`throw`调用的行号。** *This means that if the `throw new Exception( "TEST" )` line is surrounded by other operations, you have no idea at which line number the exception was actually thrown.* **这意味着，如果`throw new Exception( "TEST" )`行被其他操作包围，则您不知道实际在哪个行号上引发了异常。**

*Case 4 is similar with case 2 because the line number of the original exception is preserved, but is not a real rethrow because it changes the type of the original exception.* **情况4与情况2类似，因为保留了原始异常的行号，但不是真正的重新抛出，因为它更改了原始异常的类型。**

[How to rethrow InnerException without losing stack trace in C]: https://oldbug.net/q/eVx/How-to-rethrow-InnerException-without-losing-stack-trace-in-C
[https_stackoom.com_question_eVx_C-_InnerException]: https://stackoom.com/question/eVx/%E5%A6%82%E4%BD%95%E5%9C%A8%E4%B8%8D%E4%B8%A2%E5%A4%B1C-%E4%B8%AD%E7%9A%84%E5%A0%86%E6%A0%88%E8%B7%9F%E8%B8%AA%E7%9A%84%E6%83%85%E5%86%B5%E4%B8%8B%E6%8A%9B%E5%87%BAInnerException
[ExceptionDispatchInfo]: http://msdn.microsoft.com/en-us/library/system.runtime.exceptionservices.exceptiondispatchinfo.aspx