vc++ 调用winapi调节屏幕亮度（增加win7代码demo)

1.关于

• 代码是通过测试的，测试环境： win7 + MFC
• 为什么要发在这里？ 区别于上一篇随笔。 MD排版更顺眼
• demo 会放到 这里
• 更正了上一篇随笔中的代码错误

2.头文件

#include <physicalmonitorenumerationapi.h>
#include <highlevelmonitorconfigurationapi.h>

3.lib库文件

#pragma comment(lib, "Dxva2.lib")

4.类头文件

#pragma once

//
#include <physicalmonitorenumerationapi.h>
#include <highlevelmonitorconfigurationapi.h>

class pm_monitor_brightness
{
public:
    pm_monitor_brightness(void);
    virtual ~pm_monitor_brightness();

    /*
    @brief: 增加亮度
    @param：const unsigned int offset - 步长，最大为100， 若超过100，将亮度设置为最大
    @return： int
            0 - 成功
            1 - 失败，设置失败
    */
    int increase(const unsigned int offset = 10);

    /*
    @brief: 降低亮度
    @param：const unsigned int offset - 步长，最大为100， 若超过100，将亮度设置为低
    @return： int
            0 - 成功
            1 - 失败，设置失败
    */
    int decrease(const unsigned int offset = 10);

private:

    // 设置屏幕亮度
    void set_monitor_brightness(const unsigned int bright);

    void init();

private:
    enum
    {
        max_offset_100 = 100,

    };

    struct pm_brightness_val
    {
        // 当前亮度值
        int     _cur;
        // 显示器最大亮度
        int     _max;
        // 显示器亮度最低值
        int     _min;

        void zero()
        {
            memset(this, 0, sizeof(pm_brightness_val));
        }

        pm_brightness_val()
        {
            zero();
        }
    };

    //
    BOOL        _is_init_success;
    HANDLE      _handle_cur_monitor;

    HMONITOR    _monitor;
    DWORD       _physical_monitor_number;

    LPPHYSICAL_MONITOR   _physical_monitor;
    //
    pm_brightness_val   _brightness_val;

};

5.类源文件

#include "stdafx.h"

#include "pm_monitor_brightness.h"
#include <winuser.h>

pm_monitor_brightness::pm_monitor_brightness()
    : _is_init_success(FALSE)
    , _handle_cur_monitor(NULL)
    , _monitor(NULL)
    , _physical_monitor_number(0)
    , _physical_monitor(NULL)
{
    init();
}

pm_monitor_brightness::~pm_monitor_brightness()
{
    if (NULL != _physical_monitor)
        DestroyPhysicalMonitors(_physical_monitor_number, _physical_monitor);

    if (NULL != _physical_monitor)
    {
        free(_physical_monitor);
        _physical_monitor = NULL;
    }
}

int pm_monitor_brightness::increase(const unsigned int offset/*=10*/)
{
    pm_brightness_val& param = _brightness_val;

    // 没有初始化成功
    if (!_is_init_success)
        return 1;

    // 已经打到最大值
    if (param._cur == param._max)
        return 0;

    param._cur = (max_offset_100 == offset) ? param._max : (param._cur + offset);
    if (param._cur > param._max)
        param._cur = param._max;

    set_monitor_brightness(param._cur);

    return 0;
}

int pm_monitor_brightness::decrease(const unsigned int offset/* = 10 */)
{
    pm_brightness_val& param = _brightness_val;

    // 没有初始化成功
    if (!_is_init_success)
        return 1;

    // 已经打到最大值
    if (param._cur == param._min)
        return 0;

    param._cur = (max_offset_100 == offset) ? param._max : (param._cur - offset);
    if (param._cur < param._min)
        param._cur = param._min;

    set_monitor_brightness(param._cur);

    return 0;
}

// 设置屏幕亮度
void pm_monitor_brightness::set_monitor_brightness(const unsigned int bright)
{
    if (_is_init_success)
        SetMonitorBrightness(_handle_cur_monitor, bright);
}

void pm_monitor_brightness::init()
{
    _monitor = ::MonitorFromWindow(NULL, MONITOR_DEFAULTTOPRIMARY);

    _is_init_success = GetNumberOfPhysicalMonitorsFromHMONITOR(_monitor, &_physical_monitor_number);

    if (_is_init_success)
    {
        _physical_monitor = (LPPHYSICAL_MONITOR)malloc(_physical_monitor_number * sizeof(LPPHYSICAL_MONITOR));
        if (NULL != _physical_monitor)
        {
            _is_init_success = GetPhysicalMonitorsFromHMONITOR(_monitor, _physical_monitor_number, _physical_monitor);
            if (_is_init_success)
            {
                DWORD   max_val = 0;
                DWORD   cur_val = 0;
                DWORD   min_val = 0;

                HANDLE ppp = _physical_monitor[0].hPhysicalMonitor;
                _is_init_success = GetMonitorBrightness(ppp, &min_val, &cur_val, &max_val);

                _brightness_val._cur = cur_val;
                _brightness_val._max = max_val;
                _brightness_val._min = min_val;

                _handle_cur_monitor = ppp;
            }
        }
		else
		{
			_is_init_success = false;
		}
    }
}

6.调用

• 6.1 亮度+

_ctrl_brightness.increase(10);

• 6.2 亮度-

_ctrl_brightness.decrease(10);

7.更正后，编译结果