调用类的函数，出错，求解！
这个代码是新建的UNIT5.H

C/C++ code

//---------------------------------------#pragma hdrstop#include "Unit5.h"//---------------------------------------#pragma package(smart_init)void ClosePro(void){  Application->Terminate();}

我在UNIT3的 已经USES了UNIT5.H

但是我在UNIT3 调用

C/C++ code

 //---------------------------------------#include <vcl.h>#pragma hdrstop#include "Unit3.h"#include "Unit5.h"//---------------------------------------#pragma package(smart_init)#pragma link "Unit2"#pragma resource "*.dfm"TFmain *Fmain;//---------------------------------------__fastcall TFmain::TFmain(TComponent* Owner)    : TFbase(Owner){}//---------------------------------------void __fastcall TFmain::SpeedButton1Click(TObject *Sender){  ClosePro();}

这句代码的时候。显出
E2451 Undefined symbol 'ClosePro'

[解决办法]
我测试过了，这样可以，你对照下unit5的代码
unt5.h文件
#ifndef Unit5H
#define Unit5H
extern void ClosePro(void);
#endif
----------
unit5.cpp文件
#pragma hdrstop

#include <Forms.hpp>
#include "Unit5.h"
#pragma package(smart_init)

void ClosePro(void)
{
Application->Terminate();
}