how to move dialog which dose not have a caption.html

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<H1>How to move dialog which dose not have a caption</H1>
<H2>Introduction</H2>
<P nd="1">This article is aimed at the beginners and presents two ways to move a 
dialog which does not have a caption by dragging its client area.</P>
<H2>1. WM_SYSCOMMAND message</H2>
<P nd="2">Sending the <CODE nd="3">WM_SYSCOMMAND</CODE> message starts the move 
operation.
Add the following code to handle the mouse down event:</P><PRE nd="4">BEGIN_MSG_MAP(CMainDlg)
    ...
    MESSAGE_HANDLER(WM_LBUTTONDOWN, OnLButtonDown)
END_MSG_MAP()

LRESULT OnLButtonDown(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
{
    SendMessage(WM_SYSCOMMAND, SC_MOVE|0x0002);        
    return 0;
}
</PRE>
<P nd="5">One note though: specifying just <CODE nd="6">SC_MOVE</CODE> in a 
<CODE nd="7">WM_SYSCOMMAND</CODE> message tells Windows that you are moving the 
dialog by using the keyboard. To indicate that you want to move the dialog by 
using the mouse, you must specify <CODE nd="8">SC_MOVE|0x0002</CODE>.</P>
<H2>2. WM_NCHITTEST message</H2>
<P nd="9">The idea is to handle the <CODE nd="10">WM_NCHITTEST</CODE> message to 
return <CODE nd="11">HTCAPTION</CODE> instead of <CODE nd="12">HTCLIENT</CODE> 
when the mouse is in the client area to trick Windows to start moving the 
dialog.</P><PRE nd="13">BEGIN_MSG_MAP(CMainDlg)
    ...
    MESSAGE_HANDLER(WM_NCHITTEST, OnNcHitTest)
END_MSG_MAP()

LRESULT OnNcHitTest(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
{
    if (::DefWindowProc(m_hWnd, uMsg, wParam, lParam) == HTCLIENT && ::GetAsyncKeyState(MK_LBUTTON) < 0)
        return HTCAPTION;
                
    return 0;
}
</PRE>