HIMC hIMC;
    DWORD dwConversion, dwSentence;

    hIMC = ::ImmGetContext(m_hWnd);

    if ( ::ImmGetConversionStatus(hIMC, &dwConversion, &dwSentence) )
    {
        if ( dwConversion & IME_CMODE_NATIVE )
        {
            // 한글
        }
        else
        {
            // 영문
        }
    }

===========================================================

윈도우즈에서 한영키 세팅하는 방법입니다..
#include <imm.h>
void CMyDlg::SetEnglishMode()
{
    HIMC himc;
    DWORD dwConversion, dwSentence;
    himc = ImmGetContext(GetSafeHwnd());
    ImmGetConversionStatus(himc, &dwConversion, &dwSentence);
    ImmSetConversionStatus(himc, IME_CMODE_ALPHANUMERIC,
dwSentence);
   
}

void CMyDlg::SetHangulMode()
{
    HIMC himc;
    DWORD dwConversion, dwSentence;
    himc = ImmGetContext(GetSafeHwnd());
    ImmGetConversionStatus(himc, &dwConversion, &dwSentence);
    if (!(dwConversion & IME_CMODE_HANGUL))
        ImmSetConversionStatus(himc, dwConversion |
IME_CMODE_HANGUL, dwSentence);
   
}

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

void CMainFrame::SetIMCMode(bool english)
{
    if(english)
    {
        // 한글모드 OFF
        HIMC hIMC;
        DWORD dwConv, dwSent;

        hIMC = ImmGetContext(GetSafeHwnd());
        ImmGetConversionStatus(hIMC, &dwConv, &dwSent);

        dwConv &= ~IME_CMODE_LANGUAGE;

        ImmSetConversionStatus(hIMC, dwConv, dwSent);
        ImmReleaseContext(GetSafeHwnd(), hIMC);
    }
    else   
    {
        // 한글모드 ON
        HIMC hIMC;
        DWORD dwConv, dwSent;

        hIMC = ImmGetContext(GetSafeHwnd());
        ImmGetConversionStatus(hIMC, &dwConv, &dwSent);

        ImmSetConversionStatus(hIMC, IME_CMODE_NATIVE, dwSent);
        ImmReleaseContext(GetSafeHwnd(), hIMC);       
    }
}

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

에디터 박스를 한글입력으로...
=============================================================================
#include <imm.h>
#pragma comment(lib, "imm32.lib")

// 에디터 박스를 한글입력으로 바꿔준다.
HIMC himc = ImmGetContext(GetDlgItem(IDC_ROOM_TEXTEDIT)->GetSafeHwnd());
ImmSetConversionStatus(himc, IME_CMODE_NATIVE, IME_SMODE_CONVERSATION);
ImmReleaseContext(GetDlgItem(IDC_ROOM_TEXTEDIT)->GetSafeHwnd(), himc);
=============================================================================
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