string_access.hpp

用STL的方式封装了WindowsAPI、COM调用、ACE、ATL、MFC、WTL等多种组件

/* /////////////////////////////////////////////////////////////////////////
 * File:        atlstl/string_access.hpp (formerly atlstl_string_access.h)
 *
 * Purpose:     Contains classes and functions for dealing with OLE/COM strings.
 *
 * Created:     27th May 2002
 * Updated:     13th June 2006
 *
 * Home:        http://stlsoft.org/
 *
 * Copyright (c) 2002-2006, Matthew Wilson and Synesis Software
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
 *   any contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * ////////////////////////////////////////////////////////////////////// */

/// \file atlstl/string_access.hpp
///
/// Contains classes and functions for dealing with OLE/COM strings.

#ifndef ATLSTL_INCL_ATLSTL_HPP_STRING_ACCESS
#define ATLSTL_INCL_ATLSTL_HPP_STRING_ACCESS

#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define ATLSTL_VER_ATLSTL_HPP_STRING_ACCESS_MAJOR      3
# define ATLSTL_VER_ATLSTL_HPP_STRING_ACCESS_MINOR      2
# define ATLSTL_VER_ATLSTL_HPP_STRING_ACCESS_REVISION   4
# define ATLSTL_VER_ATLSTL_HPP_STRING_ACCESS_EDIT       85
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */

/* /////////////////////////////////////////////////////////////////////////
 * Includes
 */

#ifndef ATLSTL_INCL_ATLSTL_HPP_ATLSTL
# include <atlstl/atlstl.hpp>
#endif /* !ATLSTL_INCL_ATLSTL_HPP_ATLSTL */
#ifndef STLSOFT_INCL_STLSOFT_HPP_STRING_ACCESS
# include <stlsoft/string_access.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_HPP_STRING_ACCESS */
#ifndef STLSOFT_INCL_STLSOFT_STRING_HPP_CSTRING_MAKER
# include <stlsoft/string/cstring_maker.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_STRING_HPP_CSTRING_MAKER */
#ifdef STLSOFT_UNITTEST
# include <wchar.h>
#endif /* STLSOFT_UNITTEST */

/* /////////////////////////////////////////////////////////////////////////
 * Namespace
 */

#ifndef _ATLSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
/* There is no stlsoft namespace, so must define ::atlstl */
namespace atlstl
{
# else
/* Define stlsoft::atlstl_project */

namespace stlsoft
{

namespace atlstl_project
{

# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_ATLSTL_NO_NAMESPACE */

/* /////////////////////////////////////////////////////////////////////////
 * Classes
 */

/* CWindow */

#ifdef __ATLWIN_H__
/// This class provides an intermediary object that may be returned by the
/// c_str_ptr_null() function, such that the window text of a given window
/// may be accessed as a null-terminated string.
class c_str_ptr_null_CWindow_proxy
{
private:
    typedef cstring_maker<TCHAR>            string_maker_type;
    typedef c_str_ptr_null_CWindow_proxy    class_type;

// Construction
public:
    /// Constructs an instance of the proxy from the given CWindow instance
    ///
    /// \param w The CWindow instance from which the text will be retrieved
    ss_explicit_k c_str_ptr_null_CWindow_proxy(CWindow const &w)
    {
        int length  =   (NULL == w.m_hWnd) ? 0 : w.GetWindowTextLength();

        if(length == 0)
        {
            m_buffer = NULL;
        }
        else
        {
            m_buffer = string_maker_type::alloc(length);

            if(NULL != m_buffer)
            {
                w.GetWindowText(m_buffer, length + 1);
            }
        }
    }

#ifdef STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT
    /// Move constructor
    ///
    /// This <a href = "http://synesis.com.au/resources/articles/cpp/movectors.pdf">move constructor</a>
    /// is for circumstances when the compiler does not, or cannot, apply the
    /// return value optimisation. It causes the contents of \c rhs to be
    /// transferred into the constructing instance. This is completely safe
    /// because the \c rhs instance will never be accessed in its own right, so
    /// does not need to maintain ownership of its contents.
    c_str_ptr_null_CWindow_proxy(class_type &rhs)
        : m_buffer(rhs.m_buffer)
    {
        rhs.m_buffer = 0;
    }
#else /* ? STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT */
    // Copy constructor
    c_str_ptr_null_CWindow_proxy(class_type const &rhs)
        : m_buffer(string_maker_type::dup_null(rhs.m_buffer))
    {}
#endif /* STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT */

    /// Releases any storage aquired by the proxy
    ~c_str_ptr_null_CWindow_proxy() stlsoft_throw_0()
    {
        string_maker_type::free(m_buffer);
    }

// Accessors
public:
    /// Returns a null-terminated string representing the window contents, or
    /// NULL if the window contains no text.
    operator LPCTSTR () const
    {
        return m_buffer;
    }

// Members
private:
    LPTSTR  m_buffer;

// Not to be implemented
private:
    void operator =(class_type const &rhs);
};

/// This class provides an intermediary object that may be returned by the
/// c_str_ptr() function, such that the window text of a given window may be
/// accessed as a null-terminated string.
class c_str_ptr_CWindow_proxy
{
private:
    typedef cstring_maker<TCHAR>        string_maker_type;
    typedef c_str_ptr_CWindow_proxy     class_type;

// Construction
public:
    /// Constructs an instance of the proxy from the given CWindow instance
    ///
    /// \param w The CWindow instance from which the text will be retrieved
    ss_explicit_k c_str_ptr_CWindow_proxy(CWindow const &w)
    {
        int length  =   (NULL == w.m_hWnd) ? 0 : w.GetWindowTextLength();

        if(length == 0)
        {
            m_buffer = string_maker_type::dup("");
        }
        else
        {
            m_buffer = string_maker_type::alloc(length);

            if(NULL != m_buffer)
            {
                w.GetWindowText(m_buffer, length + 1);
            }
        }
    }

#ifdef STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT
    /// Move constructor
    ///
    /// This <a href = "http://synesis.com.au/resources/articles/cpp/movectors.pdf">move constructor</a>
    /// is for circumstances when the compiler does not, or cannot, apply the
    /// return value optimisation. It causes the contents of \c rhs to be
    /// transferred into the constructing instance. This is completely safe
    /// because the \c rhs instance will never be accessed in its own right, so
    /// does not need to maintain ownership of its contents.
    c_str_ptr_CWindow_proxy(class_type &rhs)
        : m_buffer(rhs.m_buffer)
    {
        rhs.m_buffer = 0;
    }
#else /* ? STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT */
    // Copy constructor
    c_str_ptr_CWindow_proxy(class_type const &rhs)
        : m_buffer(string_maker_type::dup_null(rhs.m_buffer))
    {}
#endif /* STLSOFT_CF_MOVE_CONSTRUCTOR_SUPPORT */

    /// Releases any storage aquired by the proxy
    ~c_str_ptr_CWindow_proxy() stlsoft_throw_0()
    {
        string_maker_type::free(m_buffer);
    }

// Accessors
public:
    /// Returns a null-terminated string representing the window contents, or
    /// the empty string "" if the window contains no text.
    operator LPCTSTR () const
    {
        return (NULL == m_buffer) ? "" : m_buffer;
    }

// Members
protected:
    LPTSTR  m_buffer;

// Not to be implemented
protected:
    void operator =(class_type const &rhs);
};
#endif /* __ATLWIN_H__ */

/* /////////////////////////////////////////////////////////////////////////
 * Equivalence testing
 */

#ifdef __ATLWIN_H__
inline as_bool_t operator ==(LPCTSTR lhs, c_str_ptr_null_CWindow_proxy const &rhs)
{
    return lhs == static_cast<LPCTSTR>(rhs);
}

inline as_bool_t operator ==(c_str_ptr_null_CWindow_proxy const &lhs, LPCTSTR rhs)
{
    return static_cast<LPCTSTR>(lhs) == rhs;
}