Library

新建 Library

新建Cpp File

File1.cpp

extern "C" __declspec(dllexport) int add(int a,int b)
{
    return a+b;

}

Build

Project->Build Project1

使用

新建项目

Add New Project

Unit1.cpp

#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
#pragma comment(lib, "Project1.lib")//链接lib
extern "C" __declspec(dllimport) int add(int a,int b);//引入涵娄
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
    int c=add(10,20);//使用函数
    ShowMessage(IntToStr(c));
}
//---------------------------------------------------------------------------

说明：vcl编写的dll的调用也类似