控制usb的有关问题

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;
using System.Threading;
using System.Collections;
using System.IO;

namespace USB
{
    class Class1
    {
        //以下是调用windows的API的函数
        //获得GUID
        [DllImport("hid.dll")]
        public static extern void HidD_GetHidGuid(ref Guid HidGuid);
        Guid guidHID = Guid.Empty;
        //过滤设备，获取需要的设备
        [DllImport("setupapi.dll", SetLastError = true)]
        public static extern IntPtr SetupDiGetClassDevs(ref Guid ClassGuid, uint Enumerator, IntPtr HwndParent, DIGCF Flags);
        IntPtr hDevInfo;
        //获取设备，true获取到
        [DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern Boolean SetupDiEnumDeviceInterfaces(IntPtr hDevInfo, IntPtr devInfo, ref Guid 

interfaceClassGuid, UInt32 memberIndex, ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData);
        public struct SP_DEVICE_INTERFACE_DATA
        {
            public int cbSize;
            public Guid interfaceClassGuid;
            public int flags;
            public int reserved;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct OVERLAPPED
        {
            int Internal;
            int InternalHigh;
            int Offset;
            int OffSetHigh;
            int hEvent;
        }

        // 获取接口的详细信息 必须调用两次 第1次返回长度 第2次获取数据
        [DllImport("setupapi.dll", SetLastError = true, CharSet = CharSet.Auto)]
        private static extern bool SetupDiGetDeviceInterfaceDetail(IntPtr deviceInfoSet, ref SP_DEVICE_INTERFACE_DATA 

deviceInterfaceData, IntPtr

deviceInterfaceDetailData,
            int deviceInterfaceDetailDataSize, ref int requiredSize, SP_DEVINFO_DATA deviceInfoData);
        [StructLayout(LayoutKind.Sequential)]
        public class SP_DEVINFO_DATA
        {
            public int cbSize = Marshal.SizeOf(typeof(SP_DEVINFO_DATA));
            public Guid classGuid = Guid.Empty; // temp
            public int devInst = 0; // dumy
            public int reserved = 0;
        }

        [StructLayout(LayoutKind.Sequential, Pack = 2)]
        internal struct SP_DEVICE_INTERFACE_DETAIL_DATA
        {
            internal int cbSize;
            internal short devicePath;
        }

        public enum DIGCF
        {
            DIGCF_DEFAULT = 0x1,
            DIGCF_PRESENT = 0x2,
            DIGCF_ALLCLASSES = 0x4,
            DIGCF_PROFILE = 0x8,
            DIGCF_DEVICEINTERFACE = 0x10
        }

        //获取设备文件
        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern int CreateFile(
            string lpFileName,                            // file name
            uint dwDesiredAccess,                        // access mode
            uint dwShareMode,                            // share mode
            uint lpSecurityAttributes,                    // SD
            uint dwCreationDisposition,                    // how to create
            uint dwFlagsAndAttributes,                    // file attributes
            uint hTemplateFile                            // handle to template file
            );
        //读取设备文件
        [DllImport("Kernel32.dll", SetLastError = true)]
        private static extern bool ReadFile
            (
                IntPtr hFile,
                byte[] lpBuffer,
                uint nNumberOfBytesToRead,
                ref uint lpNumberOfBytesRead,
                IntPtr lpOverlapped
            );

        [DllImport("kernel32.dll")]
        private static extern bool WriteFile
            (
                int hFile, 
                byte[] lpBuffer, 
                int nNumberOfBytesToWriter, 
                out int lpNumberOfBytesWriten, 
                out OVERLAPPED lpOverLapped
            );


        //释放设备
        [DllImport("hid.dll")]
        static public extern bool HidD_FreePreparsedData(ref IntPtr PreparsedData);
        //关闭访问设备句柄，结束进程的时候把这个加上保险点
        [DllImport("kernel32.dll")]
        static public extern int CloseHandle(int hObject);


        int HidHandle = -1;
        public const uint GENERIC_READ = 0x80000000;
        public const uint GENERIC_WRITE = 0x40000000;
        public const uint FILE_SHARE_READ = 0x00000001;
        public const uint FILE_SHARE_WRITE = 0x00000002;
        public const int OPEN_EXISTING = 3;

        public void UsBMethod(int index)
        {
            HidD_GetHidGuid(ref guidHID); //此处获得的guidHID就是所有usb的HID吗？？？

            hDevInfo = SetupDiGetClassDevs(ref guidHID, 0, IntPtr.Zero, DIGCF.DIGCF_PRESENT | DIGCF.DIGCF_DEVICEINTERFACE);
            int bufferSize = 0;
            ArrayList HIDUSBAddress = new ArrayList();

            string devicePathName = "";
            while (true)
            {
                //获取设备，true获取到
                SP_DEVICE_INTERFACE_DATA DeviceInterfaceData = new SP_DEVICE_INTERFACE_DATA();
                DeviceInterfaceData.cbSize = Marshal.SizeOf(DeviceInterfaceData);
                bool result = false;
                //for (int i = 0; i < 3; i++)
                //{
                    result = SetupDiEnumDeviceInterfaces(hDevInfo, IntPtr.Zero, ref guidHID, (UInt32)index, ref 

DeviceInterfaceData);
                    int b = Marshal.GetLastWin32Error();
                //}
                //第一次调用出错，但可以返回正确的Size
                SP_DEVINFO_DATA strtInterfaceData = new SP_DEVINFO_DATA();
                result = SetupDiGetDeviceInterfaceDetail(hDevInfo, ref DeviceInterfaceData, IntPtr.Zero, 0, ref bufferSize, 

strtInterfaceData);
                //第二次调用传递返回值，调用即可成功
                IntPtr detailDataBuffer = Marshal.AllocHGlobal(bufferSize);
                SP_DEVICE_INTERFACE_DETAIL_DATA detailData = new SP_DEVICE_INTERFACE_DETAIL_DATA();
                detailData.cbSize = Marshal.SizeOf(typeof(SP_DEVICE_INTERFACE_DETAIL_DATA));
                Marshal.StructureToPtr(detailData, detailDataBuffer, false);
                result = SetupDiGetDeviceInterfaceDetail(hDevInfo, ref DeviceInterfaceData, detailDataBuffer, bufferSize, ref 

bufferSize, strtInterfaceData);
                if (result == false)
                {
                    break;
                }
                //获取设备路径访
                IntPtr pdevicePathName = (IntPtr)((int)detailDataBuffer + 4);
                devicePathName = Marshal.PtrToStringAuto(pdevicePathName);
                HIDUSBAddress.Add(devicePathName);
                index++;
            }

            //连接设备文件
            int aa = CT_CreateFile(devicePathName);
        }

        //建立和设备的连接
        public int CT_CreateFile(string DeviceName)
        {
            HidHandle = CreateFile(
                DeviceName,
                GENERIC_READ | GENERIC_WRITE,//读写，或者一起
                0,// | FILE_SHARE_WRITE,//共享读写，或者一起
                0,
                OPEN_EXISTING,
                0,
                0);
            int a = Marshal.GetLastWin32Error();
            if (HidHandle == -1)
            {
                return 0;
            }
            else
            {
                return 1;
            }
        }
    }
}