c#配合c++调节屏幕亮度，非伽马以及RGB方案

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <iostream>
#include <Ntddvdeo.h>
using namespace std;

#define IOCTL_VIDEO_QUERY_SUPPORTED_BRIGHTNESS  CTL_CODE(FILE_DEVICE_VIDEO, 0x125, METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_VIDEO_QUERY_DISPLAY_BRIGHTNESS 	CTL_CODE(FILE_DEVICE_VIDEO, 0x126, METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_VIDEO_SET_DISPLAY_BRIGHTNESS 		CTL_CODE(FILE_DEVICE_VIDEO, 0x127, METHOD_BUFFERED, FILE_ANY_ACCESS)


int setBrightness(int level)
{
	HANDLE h;
	DWORD nOutBufferSize = 256;
	BYTE SupportedBrightness[256];
	DWORD g_supportedLevelCount;
	DISPLAY_BRIGHTNESS DisplayBrightness;

	memset(SupportedBrightness, 0, sizeof(SupportedBrightness));

	/* use createfile function to open lcd.
	* url from microsoft about IOCTL code.
	*  http://msdn.microsoft.com/en-us/library/windows/desktop/aa372703%28v=vs.85%29.aspx
	*/

	/*
	* char* 和 wchar_t* 互相转换参考博客
	* https://www.cnblogs.com/icqw/p/4614877.html
	*/
	/*
	* c++代码参考博客
	* https://blog.csdn.net/weixin_34111819/article/details/86328019
	*/
	char temchar[] = "\\\\.\\LCD";
	char* szSour = temchar;
	WCHAR Temp[128] = { 0 };
	mbstowcs(Temp, szSour, strlen(szSour));
	h = CreateFile(Temp, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, 0);
	if (h == INVALID_HANDLE_VALUE) {
		printf("Open \\\\.\\LCD error");
		exit(1);
	}

	/* Query for display supported level */
	if (!DeviceIoControl(h, IOCTL_VIDEO_QUERY_SUPPORTED_BRIGHTNESS, NULL, 0, SupportedBrightness, nOutBufferSize, &g_supportedLevelCount, NULL)) {
		printf("IOCTL_VIDEO_QUERY_SUPPORTED_BRIGHTNESS error - %d, - buffer: %d ", g_supportedLevelCount, nOutBufferSize);
		exit(1);
	}
	if (g_supportedLevelCount == 0)  	/* 0 means not supported */
	{
		printf("\nLCD not support LEVEL COUNT", g_supportedLevelCount);
		exit(1);
	}

	DisplayBrightness.ucDisplayPolicy = 0;
	DisplayBrightness.ucACBrightness = level;
	DisplayBrightness.ucDCBrightness = level;

	/* Set display backlight level */
	nOutBufferSize = sizeof(DisplayBrightness);
	if (!DeviceIoControl(h, IOCTL_VIDEO_SET_DISPLAY_BRIGHTNESS, (DISPLAY_BRIGHTNESS*)&DisplayBrightness, nOutBufferSize, NULL, 0, &nOutBufferSize, NULL)) {
		printf("IOCTL_VIDEO_SET_SUPPORTED_BRIGHTNESS error - %d, - buffer: %d ", g_supportedLevelCount, nOutBufferSize);
		exit(1);
	}

	Sleep(500); /* delay for some time while wmi event changed */
	nOutBufferSize = sizeof(DisplayBrightness);
	if (!DeviceIoControl(h, IOCTL_VIDEO_QUERY_DISPLAY_BRIGHTNESS, NULL, 0, (DISPLAY_BRIGHTNESS*)&DisplayBrightness, nOutBufferSize, &nOutBufferSize, NULL)) {
		printf("IOCTL_VIDEO_QUERY_SUPPORTED_BRIGHTNESS error - %d, - buffer: %d ", g_supportedLevelCount, nOutBufferSize);
		exit(1);
	}
	printf("\nBrightness_AC: %d\nBrightness_DC: %d", DisplayBrightness.ucACBrightness, DisplayBrightness.ucDCBrightness);
}


int main(int argc, char* argv[]) {
	///* program with arguments support */
	//if (argc == 3 && strcmp("-b", argv[1]) == 0) {
	//	setBrightness(atoi(argv[2]));
	//}
	//else {
	//	help();
	//}
	int a;
	cin >> a;
	setBrightness(a);
	return 0;
}

编译环境是VS，众所周知VS对代码的要求相对严格。所以这位大佬的代码有些部分需要修改。在这里我会指出修改地方以及对修改的部分进行解释。

首先#include <Ntddvdeo.h>直接引用就可以了不要加前缀，VS会自动寻找这个头文件的。

	char temchar[] = "\\\\.\\LCD";
	char* szSour = temchar;
	WCHAR Temp[128] = { 0 };
	mbstowcs(Temp, szSour, strlen(szSour));
	h = CreateFile(Temp, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, 0);

其次这里的Temp参数，之前大佬的写法是直接“\\\\.\\LCD”，但是这个参数的位置是填到一个WCHAR类型的参数，所以我们要对其进行转换。在转换的过程中VS不允许使用char*指针指向一个字符串常量，所以我们要先将这个字符串常量赋值给一个字符数组，然后再用指针指向它就行了。转换的方法在另一位大佬的博客中，我在代码中已经作为注释给出地址了（感谢各个前辈们做出的贡献）。

最后我要注明一下，这个int setBrightness(int level)中的level的范围是0到100，虽然大多数情况下调到0也能看清，但是万一呢是吧，最好测试的时候别调到零。

上面的是c++代码现在让我们来做成c#模块。（这个模块文末我会放出连接，有百度云和CSDN两个连接，还有gitHub有全部的源代码）我们的思路是将C++编译成DLL模块，然后由c#引用，并在C#中封装成模块的方式来供C#调用。

c#配合c++调节屏幕亮度，非伽马以及RGB方案

猜你喜欢