blocks|key|1023504|text|如果只想在某些情况下重新引发异常，请编写|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023505|procedure+TForm3.Button1Click(Sender:+TObject);
begin
++try
++++raise+Exception.Create('Bum');
++except
++++on+E:+Exception+do
++++begin
++++++if+MyHandleException(E)+then
++++++++raise;
++++end;
++end;
end;

function+TForm3.MyHandleException(AException:+Exception):+boolean;
begin
++ShowMessage(AException.Message);
++result+:=+true/false;
end;|code-block|syntax|javascript|1023506|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you want to re-raise the exception only under certain conditions, write

<pre><code>procedure TForm3.Button1Click(Sender: TObject);
begin
 try
 raise Exception.Create('Bum');
 except
 on E: Exception do
 begin
 if MyHandleException(E) then
 raise;
 end;
 end;
end;

function TForm3.MyHandleException(AException: Exception): boolean;
begin
 ShowMessage(AException.Message);
 result := true/false;
end;
</code></pre>

blocks|key|1023533|text|在Craig+Young的帖子之后，我已经成功地使用了以下代码。您可以通过在ExceptAddr函数中使用"at“标识符来保留原始异常位置。原始异常类类型和信息也会被保留。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023534|procedure+MyHandleException(AMethod:+string);
var
++e:+Exception;
begin
++e+:=+Exception(AcquireExceptionObject);
++e.Message+:=+e.Message+%2B+'+raised+in+'+%2B+AMethod;+
++raise+e+at+ExceptAddr;
end;

try
++...
except
++MyHandleException('MyMethod');
end;|code-block|syntax|javascript|1023535|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Following on from Craig Young's post, I've used something along the lines of the following code successfully. You can preserve the original exception location by using the "at" identifier with the ExceptAddr function. The original exception class type and information is also preserved. 

<pre><code>procedure MyHandleException(AMethod: string);
var
 e: Exception;
begin
 e := Exception(AcquireExceptionObject);
 e.Message := e.Message + ' raised in ' + AMethod; 
 raise e at ExceptAddr;
end;

try
 ...
except
 MyHandleException('MyMethod');
end;
</code></pre>

blocks|key|1238209|text|您应该能够仅使用Raise命令本身来重新引发异常：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1238210|begin
++MyHandleException(E);
++Raise;
end;|code-block|syntax|javascript|1238211|entityMap^0|8|5|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You should be able to just use the <code>Raise</code> command by itself to re-raise the exception:

<pre><code>begin
 MyHandleException(E);
 Raise;
end;
</code></pre>

blocks|key|1023626|text|老话题，但是，这个解决方案呢？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023627|procedure+MyHandleException(AException:+Exception);
begin
++ShowMessage(AException.Message);
++AcquireExceptionObject;
++raise+AException;
end;

procedure+TForm1.Button1Click(Sender:+TObject);
begin
++try
++++raise+Exception.Create('Bum');
++except
++++on+E:+Exception+do
++++++MyHandleException(E);
++end;
end;|code-block|syntax|javascript|1023628|它基于Eduardo发布的第一个代码。|1023629|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Old topic but, what about this solution?

<pre><code>procedure MyHandleException(AException: Exception);
begin
 ShowMessage(AException.Message);
 AcquireExceptionObject;
 raise AException;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
 try
 raise Exception.Create('Bum');
 except
 on E: Exception do
 MyHandleException(E);
 end;
end;
</code></pre>

It's based on the first code posted by Eduardo.

blocks|key|1023649|text|这种方式对我来说很有效！|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023650|procedure+RaiseExceptionFmt(const+AFormat:+string;
++const+AArgs:+array+of+const);
begin
++raise+Exception.CreateFmt(AFormat,+AArgs)+at+ExceptAddr;
end;|code-block|syntax|javascript|1023651|我重写了我的方法，现在的加薪将和以前一样。|1023652|procedure+RaiseInternalExceptionFmt(const+AFormat:+string;
++const+AArgs:+array+of+const);
var
++LExceptionPtr:+Pointer;
begin
++LExceptionPtr+:=+AcquireExceptionObject();
++try
++++Exception(LExceptionPtr).Message+:=+Format(AFormat,+AArgs);
++++raise+Exception(LExceptionPtr)+at+ExceptAddr;
++finally
++++ReleaseExceptionObject();
++end;
end;|1023653|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

This way was working for me!

<pre><code>procedure RaiseExceptionFmt(const AFormat: string;
 const AArgs: array of const);
begin
 raise Exception.CreateFmt(AFormat, AArgs) at ExceptAddr;
end;
</code></pre>

I rewrote my method, and now the raise will be the same before.

<pre><code>procedure RaiseInternalExceptionFmt(const AFormat: string;
 const AArgs: array of const);
var
 LExceptionPtr: Pointer;
begin
 LExceptionPtr := AcquireExceptionObject();
 try
 Exception(LExceptionPtr).Message := Format(AFormat, AArgs);
 raise Exception(LExceptionPtr) at ExceptAddr;
 finally
 ReleaseExceptionObject();
 end;
end;
</code></pre>

blocks|key|1238294|text|您可以在调用处理程序之前获取异常对象，并使处理程序本身保持一个线性。然而，你仍然有很多“尝试/例外/做/结束”的负担。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1238295|Procedure+MyExceptionHandler(AException:+Exception);
Begin
++Log(AException);+//+assuming+it+accepts+an+exception
++ShowMessage(AException.Message);
++raise+AException;+//+the+ref+count+will+be+leveled+if+you+always+raise+it
End;

Procedure+TForm3.Button1Click(Sender:+TObject);
Begin
++Try
++++Foo;
++Except+On+E:Exception+Do
++++MyExceptionHandler(Exception(AcquireExceptionObject));
++End;
End;|code-block|syntax|javascript|1238296|但是，如果您只想在事件处理程序中消除重复的错误处理代码，您可以尝试这样做：|1238297|Procedure+TForm3.ShowException(AProc+:+TProc);
Begin
++Try
++++AProc;
++Except+On+E:Exception+Do+Begin
++++Log(E);
++++ShowMessage(E.Message);
++End;+End;
End;|1238298|将您的事件处理程序代码简化为：|1238299|Procedure+TForm3.Button1Click(Sender:+TObject);
Begin
++ShowException(Procedure+Begin+//+anon+method
++++Foo;+//+if+this+call+raises+an+exception,+it+will+be+handled+by+ShowException's+handler
++End);
End;|1238300|您还可以使用参数化函数使其适用于函数：|1238301|Function+TForm3.ShowException<T>(AFunc+:+TFunc<T>)+:+T;
Begin
++Try
++++Result+:=+AFunc;
++Except+On+E:Exception+Do+Begin
++++Log(E);
++++ShowMessage(E.Message);
++End;+End;
End;|1238302|并让ShowException返回值(充当passthru)：|1238303|Procedure+TForm3.Button1Click(Sender:+TObject);
Var
++V+:+Integer;
Begin
++V+:=+ShowException<Integer>(Function+:+Integer+Begin+//+anon+method
++++Result+:=+Foo;+//+if+this+call+raises+an+exception,+it+will+be+handled+by+ShowException's+handler
++End);
End;|1238304|或者甚至让anon过程直接接触外部作用域变量：|1238305|Procedure+TForm3.Button1Click(Sender:+TObject);
Var
++V+:+Integer;
Begin
++ShowException(Procedure+Begin+//+anon+method
++++V+:=+Foo;+//+if+this+call+raises+an+exception,+it+will+be+handled+by+ShowException's+handler
++End);
End;|1238306|匿名函数体内部的变量与外部作用域中定义的变量之间的交互有一些限制，但对于像这样的简单情况，您就足够了。|1238307|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|16|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|17|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|18|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1A|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|1C|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|1D|8|@]|9|@]|A|$E|F]]|$1|W|3|X|5|6|7|1E|8|@]|9|@]|A|$]]|$1|Y|3|Z|5|D|7|1F|8|@]|9|@]|A|$E|F]]|$1|10|3|11|5|6|7|1G|8|@]|9|@]|A|$]]|$1|12|3|-4|5|6|7|1H|8|@]|9|@]|A|$]]]|13|$]]

You could acquire the exception object before calling your handler and keep the handler itself one liner. However, you still have a lot of "Try/Except/Do/End" burden.

<pre><code>Procedure MyExceptionHandler(AException: Exception);
Begin
 Log(AException); // assuming it accepts an exception
 ShowMessage(AException.Message);
 raise AException; // the ref count will be leveled if you always raise it
End;

Procedure TForm3.Button1Click(Sender: TObject);
Begin
 Try
 Foo;
 Except On E:Exception Do
 MyExceptionHandler(Exception(AcquireExceptionObject));
 End;
End;
</code></pre>

However, if what you only want to do is to get rid of repetitive error handling code in event handlers, you could try this:

<pre><code>Procedure TForm3.ShowException(AProc : TProc);
Begin
 Try
 AProc;
 Except On E:Exception Do Begin
 Log(E);
 ShowMessage(E.Message);
 End; End;
End;
</code></pre>

Reducing your event handler code to this:

<pre><code>Procedure TForm3.Button1Click(Sender: TObject);
Begin
 ShowException(Procedure Begin // anon method
 Foo; // if this call raises an exception, it will be handled by ShowException's handler
 End);
End;
</code></pre>

You can also make it work for functions, using parametrized functions:

<pre><code>Function TForm3.ShowException&lt;T&gt;(AFunc : TFunc&lt;T&gt;) : T;
Begin
 Try
 Result := AFunc;
 Except On E:Exception Do Begin
 Log(E);
 ShowMessage(E.Message);
 End; End;
End;
</code></pre>

And making ShowException return a value (acting as a passthru):

<pre><code>Procedure TForm3.Button1Click(Sender: TObject);
Var
 V : Integer;
Begin
 V := ShowException&lt;Integer&gt;(Function : Integer Begin // anon method
 Result := Foo; // if this call raises an exception, it will be handled by ShowException's handler
 End);
End;
</code></pre>

Or even making the anon procedure touch directly the outer scope variable(s):

<pre><code>Procedure TForm3.Button1Click(Sender: TObject);
Var
 V : Integer;
Begin
 ShowException(Procedure Begin // anon method
 V := Foo; // if this call raises an exception, it will be handled by ShowException's handler
 End);
End;
</code></pre>

There are some limitations on the interaction of variables from inside the body of the anonymous function and the ones defined in the outer scope, but for simple cases like these, you will be more than fine.

Do you know a way to trap, log, and re-raise exception in Delphi code?
A simple example:

<pre><code>procedure TForm3.Button1Click(Sender: TObject);
begin
 try
 raise Exception.Create('Bum');
 except
 on E: Exception do
 begin
 MyHandleException(E);
 end;
 end;
end;

procedure TForm3.MyHandleException(AException: Exception);
begin
 ShowMessage(AException.Message);
 LogThis(AException.Message); 
 // raise AException; - this will access violate
end;
</code></pre>

So I need to re-raise it in the except block but I was wondering if there is a better way to write my own method to handle and (on specific conditions) to re-raise exceptions.

How should I re-raise a Delphi exception after logging it?

你知道在Delphi代码中捕获、记录和重新引发异常的方法吗？一个简单的例子：procedure TForm3.Button1Click(Sender: TObject);begin  try    raise Exception.Create('Bum');  except    on E: Exception do    begin      MyHandleException(E);    e

问如何在记录后重新引发Delphi异常？
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回答 6

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问如何在记录后重新引发Delphi异常？EN

回答 6

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问如何在记录后重新引发Delphi异常？
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