How do I find position of a Win32 control/window relative to its parent window?

Question

Given handle of a Win32 window, I need to find position of it relative to its parent window.

I know several functions (e.g.; GetWindowRect() and GetClientRect()), bu

Answer 1

Here's a very basic typedef struct based on the above answers:

typedef struct tagRectCl {
    static RECT rectOut;
    RECT RectCl(int ctrlID, HWND &hwndCtrl, HWND &ownerHwnd)
    {
    RECT rectIn;
    GetWindowRect(hwndCtrl, &rectIn); //get window rect of control relative to screen
    MapWindowPoints(NULL, ownerHwnd, (LPPOINT)&rectIn, 2);
    rectOut = rectIn;
    return rectOut;
    }
    RECT RectCl(int ctrlID)
    {
       // for rectOut already populated
       return rectOut;
    }
    };
}RectCl;

RECT RectCl::rectOut = {};

The idea being to extend ctrlID over a range of controls, where the storage for the corresponding rectOuts can be considered for a more accommodating structure.
Usage: the following returns the converted rect:

RECT rect1 = RectCl().RectCl(IDC_CTRL1, hWndCtrl, hWndOwner);

The following is a partly coded function that takes elements of both answers into something usable for dialogs - particularly for move/resizing control co-ordinates, the original reason for landing at this page.
It accepts as parameters an integral control ID from a resource or HMENU item from CreateWindow, and a handle for its container.
One should also consider whether ownerHwnd is minimized before calling the function by listening for SIZE_MINIMIZED in WM_SIZE.

BOOL ProcCtrl(int ctrlID, HWND ownerHwnd)
{
    RECT rcClient = {0};        
    HWND hwndCtrl = GetDlgItem(ownerHwnd, ctrlID);
    if (hwndCtrl)
    {
    GetWindowRect(hwndCtrl, &rcClient); //get window rect of control relative to screen
    MapWindowPoints(NULL, ownerHwnd, (LPPOINT)&rcClient,2);

    /* Set extra scaling parameters here to suit in either of the following functions
    if (!MoveWindow(hwndCtrl, rcClient.left, rcClient.top, 
    rcClient.right-rcClient.left, rcClient.bottom-rcClient.top, TRUE))
    {
        //Error;
        return FALSE;
    }
    //if (!SetWindowPos(hwndCtrl, NULL, (int)rcClient.left, (int)(rcClient.top),
    //(int)(rcClient.right - rcClient.left), (int)(rcClient.bottom - rcClient.top), SWP_NOZORDER))
    {
        //Error;
        //return FALSE;
    }
    }
    else
    {
        //hwndCtrl Error;
        return FALSE;
    }
    return TRUE;
}