设置大小写键盘 C#

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

namespace sn设置键盘大小写
{
    public partial class Form1 : Form
    {
        const uint KEYEVENTF_EXTENDEDKEY = 0x1;
        const uint KEYEVENTF_KEYUP = 0x2;

        [DllImport("user32.dll")]
        static extern short GetKeyState(int nVirtKey);
        [DllImport("user32.dll")]
        static extern void keybd_event(byte bVk, byte bScan, uint dwFlags, uint dwExtraInfo);

        public enum VirtualKeys : byte
        {
            VK_NUMLOCK = 0x90, //数字锁定键
            VK_SCROLL = 0x91,  //滚动锁定
            VK_CAPITAL = 0x14, //大小写锁定
            VK_A = 62
        }

        public Form1()
        {
            InitializeComponent();
        }

        public static bool GetState(VirtualKeys Key)
        {
            return (GetKeyState((int)Key)==1);
        }
        public static void SetState(VirtualKeys Key, bool State)
        {
            if (State != GetState(Key))
            {
                keybd_event((byte)Key, 0x45, KEYEVENTF_EXTENDEDKEY | 0, 0);
                keybd_event((byte)Key, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);
            }
        }

        //开启键盘大写
        private void btnOpenCAPITAL_Click(object sender, EventArgs e)
        {
            SetState(VirtualKeys.VK_CAPITAL, true);
        }

        //关闭键盘大写
        private void btnCloseCAPITAL_Click(object sender, EventArgs e)
        {
            SetState(VirtualKeys.VK_CAPITAL, false);
        }