c# USB通信

首先，通信流程我们先撸一边，打开USB设备-》发送数据库-》接受数据-》关闭USB设备

根据USB规范的规定，所有的USB设备都有供应商ID（VID）和产品识别码（PID），主机通过不同的VID和PID来区别不同的设备。

我们需要知道设备的VID和PID才能定位到我们需要打开的USB设备，那么我们怎么知道USB设备的VID和PID参数呢？

方法一：电脑上查看

方法二，代码查看

大家可以自己百度下，很多文章都有写。。。。。c# 查看所有USB信息

知道设备的VID和HID后，剩下的就好操作了。二话不说，直接上代码。

注意：很重要

1：大家可以网上查看其它文章，有很多USB-HID通信文章，大家可以参考和借鉴，但是实际使用过程中需要注意的是人家的文章是用于HID的设备，如果你设备不是HID的那么就用不了。

那么怎么查自己的设备是什么类型的呢？windows是通过设备接口类的GUID来区分的

常用设备接口类GUID，大家可以自己查看自己的设备是什么类别的，比如

HID： "{4D1E55B2-F16F-11CF-88CB-001111000030}";
USB_DEVICE： "{A5DCBF10-6530-11D2-901F-00C04FB951ED}";
COMPORT： "{86E0D1E0-8089-11D0-9CE4-08003E301F73}";

我们需要根据设备接口类的GUID，获取对应的设备列表，再通过VID和GUID去设备列表中匹配对应的设备，获取设备的路径，通过路径打开设备进行通信。具体的自己分析代码

using Microsoft.Win32.SafeHandles;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace TPCL.USB
{
class UsbDevice
{
#region MyRegion
private FileStream DeviceIo = null; //异步IO流
private bool is_open = false;
private IntPtr device = new IntPtr(-1);

private const int MAX_USB_DEVICES = 64;
private static IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);
//常用设备接口类GUID
private const string HidGuid = "{4D1E55B2-F16F-11CF-88CB-001111000030}";
private const string UsbDevGuid = "{A5DCBF10-6530-11D2-901F-00C04FB951ED}";
private const string UsbComPort = "{86E0D1E0-8089-11D0-9CE4-08003E301F73}";

public static void GetAllUsbDevice(ref List<string> UsbDeviceList)
{
UsbDeviceList.Clear();
Guid guid = Guid.Parse(UsbDevGuid);
IntPtr deviceInfoSet = SetupDiGetClassDevs(ref guid, 0, IntPtr.Zero, DIGCF.DIGCF_PRESENT | DIGCF.DIGCF_DEVICEINTERFACE);
if (deviceInfoSet != IntPtr.Zero)
{
SP_DEVICE_INTERFACE_DATA interfaceInfo = new SP_DEVICE_INTERFACE_DATA();
interfaceInfo.cbSize = Marshal.SizeOf(interfaceInfo);
for (uint index = 0; index < 64; index++)
{
if (SetupDiEnumDeviceInterfaces(deviceInfoSet, IntPtr.Zero, ref guid, index, ref interfaceInfo))
{
// 取得接口详细信息:第一次读取错误,但可以取得信息缓冲区的大小
int buffsize = 0;
SetupDiGetDeviceInterfaceDetail(deviceInfoSet, ref interfaceInfo, IntPtr.Zero, buffsize, ref buffsize, null);
//构建接收缓冲
IntPtr pDetail = Marshal.AllocHGlobal(buffsize);
SP_DEVICE_INTERFACE_DETAIL_DATA detail = new SP_DEVICE_INTERFACE_DETAIL_DATA();
//detail.cbSize = Marshal.SizeOf(typeof(SP_DEVICE_INTERFACE_DETAIL_DATA));
if (IntPtr.Size == 8)
detail.cbSize = 8; // for 64 bit operating systems
else
detail.cbSize = 4 + Marshal.SystemDefaultCharSize; // for 32 bit operating systems
Marshal.StructureToPtr(detail, pDetail, false);
if (SetupDiGetDeviceInterfaceDetail(deviceInfoSet, ref interfaceInfo, pDetail, buffsize, ref buffsize, null))
{
UsbDeviceList.Add(Marshal.PtrToStringAuto((IntPtr)((int)pDetail + 4)));
}
//
Marshal.FreeHGlobal(pDetail);
}
}
}
SetupDiDestroyDeviceInfoList(deviceInfoSet);
}

public int OpenUsbDevice(UInt16 vID, UInt16 pID)
{
List<string> deviceList = new List<string>();
GetAllUsbDevice(ref deviceList);
if (deviceList.Count == 0)
return 0;

string VID = string.Format("{0:X4}", vID);
string PID = string.Format("{0:X4}", pID);

foreach (string item in deviceList)
{
if (item.ToLower().Contains(VID.ToLower()) && item.ToLower().Contains(PID.ToLower())) //指定设备
{
Debug.WriteLine(item);
if (is_open == false)
{
device = CreateFile(item, DESIREDACCESS.GENERIC_READ | DESIREDACCESS.GENERIC_WRITE,
0, 0, CREATIONDISPOSITION.OPEN_EXISTING, 0x40000000, 0);

if (device != INVALID_HANDLE_VALUE)
{
Debug.WriteLine("open");
DeviceIo = new FileStream(new SafeFileHandle(device, false), FileAccess.ReadWrite,40,true);
//DeviceIo = new FileStream(new SafeFileHandle(device, false), FileAccess.ReadWrite);
this.is_open = true;
return 1;
}
CloseHandle(device);
}
}
}
return 0;
}

public void CloseDevice()
{
if (is_open == true)
{
is_open = false;
DeviceIo.Close();
CloseHandle(device);
}
}

public void Send(string dataString)
{
if (DeviceIo == null)
{
Debug.WriteLine("USB Device not open");
return;
}
byte[] data = Encoding.GetEncoding("GBK").GetBytes(dataString); //打印机支持GBK中文
// byte[] data = System.Text.Encoding.ASCII.GetBytes(dataString);
DeviceIo.Write(data, 0, data.Length);
}

public void Read()
{
//DeviceIo.Read
}

public bool GetDeviceState()
{
return is_open;
}

#endregion

#region Win32_api
public enum DIGCF
{
DIGCF_DEFAULT = 0x00000001, //只返回与系统默认设备相关的设备。
DIGCF_PRESENT = 0x00000002, //只返回当前存在的设备。
DIGCF_ALLCLASSES = 0x00000004, //返回所有已安装的设备。如果这个标志设置了，ClassGuid参数将被忽略
DIGCF_PROFILE = 0x00000008, //只返回当前硬件配置文件中的设备。
DIGCF_DEVICEINTERFACE = 0x00000010 //返回所有支持的设备。
}

/// <summary>
/// 接口数据定义
/// </summary>
public struct SP_DEVICE_INTERFACE_DATA
{
public int cbSize;
public Guid interfaceClassGuid;
public int flags;
public int reserved;
}
/// <summary>
/// 定义设备实例，该实例是设备信息集的成员
/// </summary>
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;
}

internal struct SP_DEVICE_INTERFACE_DETAIL_DATA
{
internal int cbSize;
internal short devicePath;
}

/// <summary>
/// 获取USB-HID设备的设备接口类GUID，即{4D1E55B2-F16F-11CF-88CB-001111000030}
/// </summary>
/// <param name="HidGuid"></param>
[DllImport("hid.dll")]
private static extern void HidD_GetHidGuid(ref Guid HidGuid);

/// <summary>
/// 获取对应GUID的设备信息集(句柄)
/// </summary>
/// <param name="ClassGuid">设备设置类或设备接口类的guid</param>
/// <param name="Enumerator">指向以空结尾的字符串的指针，该字符串提供PNP枚举器或PNP设备实例标识符的名称</param>
/// <param name="HwndParent">用于用户界面的顶级窗口的句柄</param>
/// <param name="Flags">一个变量，指定用于筛选添加到设备信息集中的设备信息元素的控制选项。</param>
/// <returns>设备信息集的句柄</returns>
[DllImport("setupapi.dll", SetLastError = true)]
private static extern IntPtr SetupDiGetClassDevs(ref Guid ClassGuid, uint Enumerator, IntPtr HwndParent, DIGCF Flags);

/// <summary>
/// 根据句柄，枚举设备信息集中包含的设备接口。
/// </summary>
/// <param name="deviceInfoSet"></param>
/// <param name="deviceInfoData"></param>
/// <param name="interfaceClassGuid"></param>
/// <param name="memberIndex"></param>
/// <param name="deviceInterfaceData"></param>
/// <returns></returns>
[DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern Boolean SetupDiEnumDeviceInterfaces(IntPtr deviceInfoSet, IntPtr deviceInfoData, ref Guid interfaceClassGuid, UInt32 memberIndex, ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData);

/// <summary>
/// 获取接口详细信息，在第一次主要是读取缓存信息,第二次获取详细信息(必须调用两次)
/// </summary>
/// <param name="deviceInfoSet">指向设备信息集的指针，它包含了所要接收信息的接口。该句柄通常由SetupDiGetClassDevs函数返回。</param>
/// <param name="deviceInterfaceData">返回数据</param>
/// <param name="deviceInterfaceDetailData"></param>
/// <param name="deviceInterfaceDetailDataSize"></param>
/// <param name="requiredSize"></param>
/// <param name="deviceInfoData"></param>
/// <returns></returns>
[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);

/// <summary>
/// 删除设备信息并释放内存。
/// </summary>
/// <param name="HIDInfoSet"></param>
/// <returns></returns>
[DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern Boolean SetupDiDestroyDeviceInfoList(IntPtr deviceInfoSet);
#endregion

#region Open_Device
/// <summary>
/// 访问权限
/// </summary>
static class DESIREDACCESS
{
public const uint GENERIC_READ = 0x80000000;
public const uint GENERIC_WRITE = 0x40000000;
public const uint GENERIC_EXECUTE = 0x20000000;
public const uint GENERIC_ALL = 0x10000000;
}
/// <summary>
/// 如何创建
/// </summary>
static class CREATIONDISPOSITION
{
public const uint CREATE_NEW = 1;
public const uint CREATE_ALWAYS = 2;
public const uint OPEN_EXISTING = 3;
public const uint OPEN_ALWAYS = 4;
public const uint TRUNCATE_EXISTING = 5;
}

/// <summary>
///
/// </summary>
/// <param name="lpFileName">普通文件名或设备文件名</param>
/// <param name="desiredAccess">访问模式（写/读） GENERIC_READ、GENERIC_WRITE </param>
/// <param name="shareMode">共享模式</param>
/// <param name="securityAttributes">指向安全属性的指针</param>
/// <param name="creationDisposition">如何创建</param>
/// <param name="flagsAndAttributes">文件属性</param>
/// <param name="templateFile">用于复制文件句柄</param>
/// <returns></returns>
[DllImport("kernel32.dll", SetLastError = true)]
private static extern IntPtr CreateFile(string lpFileName, uint desiredAccess, uint shareMode, uint securityAttributes, uint creationDisposition, uint flagsAndAttributes, uint templateFile);

/// <summary>
/// 关闭
/// </summary>
/// <param name="hObject">Handle to an open object</param>
/// <returns></returns>
[DllImport("kernel32.dll")]
private static extern int CloseHandle(IntPtr hObject);

#endregion
}
}

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版权声明：本文为CSDN博主「毛小民°」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/xiejie0226/article/details/102582053