HookImpl

今天试着写了一个HOOKIMPL  WTL用的,感觉还好..就是只能单实例...以后再加

#pragma once

template <typename T>
class ATL_NO_VTABLE CHookImpl
{
    UINT WM_HOOKIMPL;
    HHOOK m_hHook;
    static T* m_pT;
public:
    CHookImpl( UINT nMsgHook = WM_USER + 0x3000 ) : WM_HOOKIMPL( nMsgHook ), m_hHook( NULL )
    {
        m_pT = static_cast<T*>( this );
    }

    ~CHookImpl()
    {
        if ( m_hHook )
        {
            ::UnhookWindowsHookEx( m_hHook );
        }
    }

    bool InstallHook( int nHookType )
    {
        if ( m_hHook )
        {
            if ( !::UnhookWindowsHookEx( m_hHook ) )
            {
                return false;
            }
        }

        m_hHook = ::SetWindowsHookEx( nHookType, _FunHookProc, ModuleHelper::GetModuleInstance(), 0 );

        return m_hHook != NULL;
    }

    bool RemoveHook()
    {
        if ( m_hHook && ::UnhookWindowsHookEx( m_hHook ) )
        {
            m_hHook = NULL;
            return true;
        }

        return false;
    }

    static LRESULT CALLBACK _FunHookProc( int nCode, WPARAM wParam, LPARAM lParam )
    {
        LRESULT lRet;

        lRet = ::CallNextHookEx( m_pT->m_hHook, nCode, wParam, lParam );

        if ( nCode == HC_ACTION )
        {
            ::SendMessage( m_pT->m_hWnd, m_pT->WM_HOOKIMPL, wParam, lParam );
        }

        return lRet;
    }


    BEGIN_MSG_MAP( CHookImpl<T> )
        MESSAGE_HANDLER( WM_HOOKIMPL, OnHookAction )
    END_MSG_MAP()


    LRESULT OnHookAction( UINT /*uMsg*/, WPARAM wParam, LPARAM lParam, BOOL& bHandled )
    {
        m_pT->HookAction( wParam, lParam );
        bHandled = TRUE;
        return 0;
    }

    void HookAction( WPARAM /*wParam*/, LPARAM /*lParam*/ )
    {
        ATLASSERT( FALSE );
    }
};

template<typename T>
T* CHookImpl<T>::m_pT = NULL;