CException::Delete
void CException::Delete();
說明：
此函式檢查CException對象是否在堆頂建立，如果在堆頂建立，對該對象做刪除操作。當刪除該CException對象後，使用Delete成員函式刪除異常。不要直接使用刪除操作，因為CException對象可能是一個全局對象或者是在棧中創建的。
你可以指定當對象被創建時是否應被刪除。要了解更多信息，請參閱CException::CException。
如果使用C++“試抓”（try-catch）機制，只需調用Delete。如果使用MFC的TRY和CATCH宏，這些宏會自動調用此成員函式。
MSDN 解釋如下：
CException::Delete
void CException::Delete( );
Remarks
This function checks to see if the CException object was created on the heap, and if so, it calls the delete operator on the object. When deleting a CException object, use the Delete member function to delete the exception. Do not use the delete operator directly, because the CException object may be a global object or have been created on the stack.
You can specify whether the object should be deleted when the object is constructed. For more information, see CException::CException.
You only need to call Delete if you are using the C++ try-catch mechanism. If you are using the MFC macros TRY and CATCH, then these macros will automatically call this function.
