DynamicLib

struct ShareUser32 {
    ShareUser32();
    DllFunc<HWND()> GetDesktopWindow;
    DllFunc<BOOL(HWND, LPRECT)> GetClientRect;
};

ShareUser32::ShareUser32()
    : GetClientRect("User32.dll", "GetClientRect", DllFuncType::DTF_STDCALL)
    , GetDesktopWindow("User32.dll", "GetDesktopWindow", DllFuncType::DTF_STDCALL)
{}

struct StaticUser32 {
    static DllFunc<HWND()> GetDesktopWindow;
    static DllFunc<BOOL(HWND, LPRECT)> GetClientRect;
};

DllFunc<HWND()> StaticUser32::GetDesktopWindow("User32.dll", "GetDesktopWindow", DllFuncType::DTF_STDCALL);
DllFunc<BOOL(HWND, LPRECT)> StaticUser32::GetClientRect("User32.dll", "GetClientRect", DllFuncType::DTF_STDCALL);

struct DllTest {
    DllFunc<int()> fnDllTest;
    DllTest() : fnDllTest("fnDllTest") {}
};

int main(int argc, char* argv[]) {

#ifdef WIN32

    RECT rcWnd;

    // 动态存储懒加载
    ShareUser32 mUser32;
    HWND hWnd = mUser32.GetDesktopWindow();
    mUser32.GetClientRect(hWnd, &rcWnd);

    // 静态存储懒加载
    hWnd = StaticUser32::GetDesktopWindow();
    StaticUser32::GetClientRect(hWnd, &rcWnd);

#endif

    char buffer[256];
    _getcwd(buffer, sizeof(buffer));

    //////////////////////////////////////////////////////////////////////////

    DllTest DllTestInst;

    // 动态存储切换加载资源
#ifdef WIN32
    DllTestInst.fnDllTest.Load("DllTestOne.dll");
#else
    std::string OnePath(buffer);
#ifdef __APPLE__
    OnePath.append("/DllTestOne.dylib");
#else
    OnePath.append("/DllTestOne.so");
#endif
    DllTestInst.fnDllTest.Load(OnePath.c_str());
#endif

DllTestInst.fnDllTest();
DllTestInst.fnDllTest.Free();

    // 动态存储切换加载资源
#ifdef WIN32
    DllTestInst.fnDllTest.Load("DllTestTwo.dll");
#else
    std::string TwoPath(buffer);
#ifdef __APPLE__
    TwoPath.append("/DllTestTwo.dylib");
#else
    TwoPath.append("/DllTestTwo.so");
#endif
    DllTestInst.fnDllTest.Load(TwoPath.c_str());
#endif
    DllTestInst.fnDllTest();
    DllTestInst.fnDllTest.Free();

    return 0;
}