C# 通过热键控制显示器开关

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace OpenMonitor
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
HotKey.RegisterHotKey(this.Handle, 100, 0, Keys.F4);
HotKey.RegisterHotKey(this.Handle,101,0,Keys.F5);
}

class HotKey
{
// 如果函数执行成功，返回值不为0。
// 如果函数执行失败，返回值为0。要得到扩展错误信息，调用GetLastError。
[DllImport("user32.dll ", SetLastError = true)]
public static extern bool RegisterHotKey(
IntPtr hWnd, // 要定义热键的窗口的句柄
int id, // 定义热键ID（不能与其它ID重复）
KeyModifiers fsModifiers, // 标识热键是否在按Alt、Ctrl、Shift、Windows等键时才会生效
Keys vk // 定义热键的内容
);

[DllImport("user32.dll ", SetLastError = true)]
public static extern bool UnregisterHotKey(
IntPtr hWnd, // 要取消热键的窗口的句柄
int id // 要取消热键的ID
);

// 定义了辅助键的名称（将数字转变为字符以便于记忆，也可去除此枚举而直接使用数值）
[Flags()]
public enum KeyModifiers
{
None = 0,
Alt = 1,
Ctrl = 2,
Shift = 4,
WindowsKey = 8
}
}

protected override void WndProc(ref Message m)
{
const int WM_HOTKEY = 0x0312;
// 按快捷键
switch (m.Msg)
{
case WM_HOTKEY:
switch (m.WParam.ToInt32())
{
case 100:
MonitorHelper.TurnOn();
break;
case 101:
MonitorHelper.TurnOff();
break;
}
break;
}
base.WndProc(ref m);
}

class MonitorHelper
{
public static void TurnOn()
{
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, -1);
}

public static void TurnOff()
{
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, 2);
}

[DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);

private static readonly IntPtr HWND_BROADCAST = new IntPtr(0xffff);
private const uint WM_SYSCOMMAND = 0x0112;
private const int SC_MONITORPOWER = 0xf170;
}
}
}