c++ builder的virtual函数怎么写(小弟分不多了,请见谅)

在头文件声明
class a
{
public:
__fastcall a();
virtual __fastcall ~a();
}
在cpp文件定义
__fastcall a::a(){
}
virtual __fastcall a::~a()
为什么会出现这样的错误:
[C++ Error] CreateShape.cpp(15): E2092 Storage class 'virtual' is not allowed here
定义其他的虚函数也会出现这样的情况。
我编程时间不长,想请教virtual函数应该怎么写
[359 byte] By [oasis92] at [2008-1-9]
# 1
cpp里面不用再写virtual这个标识
proton-欲速则不达! at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...
# 2
应该是楼上说的那样
yangyaoxing-sihan at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...
# 3
__fastcall a::~a()
Y___Y-一叶障目 at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...
# 4
virtual标识只需在声明处就可以了,定义时不再需要标识它
controstr-小菜鸟 at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...
# 5
virtual void __fastcall abc() { }

virtual int __fastcall abcd() { return 1; }

sczyq-我又........... at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...
# 6
问题解决了,谢谢
oasis92 at 2007-10-18 > top of Msdn China Tech,C++ Builder,基础类...