RealChildWindowFromPoint为何编译时找不到声明？

[galey]

我在自己的程序中用刀函数RealChildWindowFromPoint，但是编译的时候系统总是提示RealChildWindowFromPoint' : undeclared identifier
和cannot convert from 'int' to 'struct HWND__ *'的编译错误。
RealChildWindowFromPoint在Winuser.h中的确有定义，但是为什么找不到呢？我的环境是WIN2000 server +sp4，VC6.0+sp4。
希望哪位大侠指点一二。

[FlyYang]

你包含Windows.h看看

---------
++C++
---------

[galey]

我包含了Windows.h，结果还是一样。
好像一般的情况下Windows.h，喝Winuser.h都不需要包含的呀，MFC生成框架文件自己本身就包含了。

[dlfour]

把你的代码贴出来看看

[galey]

现在的情况是直接用MFC生成框架，只有这么几句代码，最简单的测试：
HWND hwnd;
POINT ptP;

//hwnd,ptP的都有值

RealChildWindowFromPoint(hwnd,ptP);

然后编译在上面这句就不能通过了，提示RealChildWindowFromPoint' : undeclared identifier这样的错误。

而且不管是否包含windows.h 和 winuser.h的结果都是一样的。

[flyelf]

就用LoadLibrary和GetProcAddr来获取这个地址，然后使用

[arvid_gs]

这样搞把，好像2000中这个函数看不到了，这是个例子看看，我还有全部代码，如果你要，发消息给我！
typedef HWND (WINAPI *REALCHILDWINDOWFROMPOINT)(HWND hwndParent, POINT ptParentClientCoords);

CWnd* CMiniSpyDlg::RealWindowFromPoint(CPoint ptHitTest)
{
CWnd* pWnd = WindowFromPoint(ptHitTest);

if (pWnd && (pWnd->GetStyle() & WS_CHILD))
{
// now check that another control is not being masked by say a group box
CWnd* pParent = pWnd->GetParent();

if (pParent)
{
// have to call
HMODULE hUser32 = ::LoadLibrary("User32.dll");

if (hUser32)
{
// note this function is not available under win95 so we also have a fallback
REALCHILDWINDOWFROMPOINT fnRealWndFromPoint = (REALCHILDWINDOWFROMPOINT)GetProcAddress(hUser32, "RealChildWindowFromPoint");

if (fnRealWndFromPoint)
{
// convert to parent client coords
pParent->ScreenToClient(&ptHitTest);

HWND hHit = fnRealWndFromPoint(*pParent, ptHitTest);

if (hHit)
pWnd = CWnd::FromHandle(hHit);
}
else
{
// iterate all the child controls of the parent until we hit one which
// does not return HTTRANSPARENT or HTNOWHERE to WM_NCHITTEST
CWnd* pChild = pParent->GetWindow(GW_CHILD);
ASSERT (pChild);

while (pChild)
{
UINT uHitTest = pChild->SendMessage(WM_NCHITTEST, 0, MAKELPARAM(ptHitTest.x, ptHitTest.y));

if ((int)uHitTest > 0)
{
pWnd = pChild;
break;
}

pChild = pChild->GetNextWindow();
}
}
}
}
}

return pWnd;
}

[galey]

我是这样调用的：
HWND (*ptfnRealChildWindowFromPoint)(HWND hwndParent,POINT ptParentClientCoords);

HMODULE hMdl = LoadLibrary("USER32.DLL");
ptfnRealChildWindowFromPoint = (HWND (*)(HWND hwndParent,POINT ptParentClientCoords))GetProcAddress(hMdl,"RealChildWindowFromPoint");
hWndChild = ptfnRealChildWindowFromPoint(*phWnd, ptCooChild);

但是一执行到上面这一句就报错：
The value of ESP was not properly saved across a function call. This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention.
真的是我声明错误吗？还是函数的调用转换错误。

[arvid_gs]

typedef HWND (WINAPI *REALCHILDWINDOWFROMPOINT)(HWND hwndParent, POINT ptParentClientCoords);
HMODULE hUser32 = ::LoadLibrary("User32.dll");
if (hUser32)
{
REALCHILDWINDOWFROMPOINT fnRealWndFromPoint = (REALCHILDWINDOWFROMPOINT)GetProcAddress(hUser32, "RealChildWindowFromPoint");
}

[flyelf]

你的代码对RealChildWindowFromPoint声明有问题，应该如 arvid_gs(west) 所说的定义
typedef HWND (WINAPI *REALCHILDWINDOWFROMPOINT)(HWND, POINT);
其中winapi不能少

[galey]

谢谢arvid_gs(west)：能把源代码发给我看看吗。
[e-mail]，结贴一定给分。

[dxp]

是的
WINAPI声明决定了函数参数压栈顺序

[galey]

OK，问题解决，在这里感谢所有回帖的大侠们。
结贴，给分。
谢谢！谢谢！谢谢！谢谢！