C#串口通信—向串口发送数据，同步接收返回数据
最近写C#串口通信程序，系统是B/S架构。SerialPort类有一个DataReceived事件，用来接收串口返回的数据，但这种方式在C/S架构下很好用，但B/S就不好处理了。所以写了一个同步模式接收返回数据的方法，不使用DataReceived事件。经过测试，可以正常使用。
一、MachineFactory类
为什么使用工厂类：售货机由不止一个厂家提供，接口协议都不一样。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;
using System.IO;
using System.IO.Ports;
namespace IMachineDll
{
///
/// 售货机工厂类
///
public class MachineFactory
{
///
/// 货机接口缓存
///
private static Dictionary dicMachine = new Dictionary();
///
/// 锁变量
///
public static object _lock = new object();
///
/// 创建售货机类
///
/// DLL物理路径
/// DLL名称(不含扩展名)，命名空间必须为DLL名称加“Dll”后缀，类名必须和DLL名称相同
/// 串口名称，如：COM1
public static IMachine Create(string path, string dllName, string com)
{
if (!dicMachine.ContainsKey(dllName)
|| dicMachine[dllName] == null)
{
using (FileStream fs = new FileStream(path + dllName + ".dll", FileMode.Open, FileAccess.Read))
{
using (MemoryStream ms = new MemoryStream())
{
byte[] byteArray = new byte[4096];
while (fs.Read(byteArray, 0, byteArray.Length) > 0)
{
ms.Write(byteArray, 0, byteArray.Length);
}
Assembly assembly = Assembly.Load(ms.ToArray());
dicMachine[dllName] = (IMachine)assembly.CreateInstance(dllName + "Dll." + dllName, false, BindingFlags.Default, null, new object[] { com }, null, null);
}
}
}
return dicMachine[dllName];
}
}
}
二、Machine类
1、变量与构造函数
///
/// 串口资源
///
private SerialPort serialPort = null;
public Machine(string com)
{
serialPort = new SerialPort(com, 9600, Parity.None, 8, StopBits.One);
serialPort.ReadBufferSize = 1024;
serialPort.WriteBufferSize = 1024;
}2、向串口发送数据，同步接收返回数据的方法：
///
/// 向串口发送数据，读取返回数据
///
/// 发送的数据
/// 返回的数据
private byte[] ReadPort(byte[] sendData)
{
lock (MachineFactory._lock)
{
//打开连接
if (!serialPort.IsOpen) serialPort.Open();
//发送数据
serialPort.Write(sendData, 0, sendData.Length);
//读取返回数据
DateTime dt = DateTime.Now;
while (serialPort.BytesToRead == 0)
{
Thread.Sleep(1);
if (DateTime.Now.Subtract(dt).TotalMilliseconds > 5000) //如果5秒后仍然无数据返回，则视为超时
{
throw new Exception("主版无响应");
}
}
Thread.Sleep(50);
byte[] recData = new byte[serialPort.BytesToRead];
serialPort.Read(recData, 0, recData.Length);
//关闭连接
if (serialPort.IsOpen) serialPort.Close();
return recData;
}
}优化版：
///
/// 向串口发送数据，读取返回数据
///
/// 发送的数据
/// 返回的数据
private byte[] ReadPort(byte[] sendData)
{
lock (MachineFactory._lock)
{
//打开连接
if (!serialPort.IsOpen) serialPort.Open();
//发送数据
serialPort.Write(sendData, 0, sendData.Length);
//读取返回数据
DateTime dt = DateTime.Now;
while (serialPort.BytesToRead < 2)
{
Thread.Sleep(1);
if (DateTime.Now.Subtract(dt).TotalMilliseconds > 5000) //如果5秒后仍然无数据返回，则视为超时
{
throw new Exception("主版无响应");
}
}
List recList = new List();
byte[] recData = new byte[serialPort.BytesToRead];
serialPort.Read(recData, 0, recData.Length);
recList.AddRange(recData);
int length = recData[1] + 3; //报文数据总长度
while (recList.Count < length)
{
if (serialPort.BytesToRead > 0)
{
recData = new byte[serialPort.BytesToRead];
serialPort.Read(recData, 0, recData.Length);
recList.AddRange(recData);
}
Thread.Sleep(1);
}
//关闭连接
if (serialPort.IsOpen) serialPort.Close();
return recList.ToArray();
}
} 3、发送联机指令：
///
/// 联机
///
/// 传出错误信息
/// 联机是否成功
public bool Connect(out string msg)
{
byte[] sendData = new byte[] { 0x01, 0x01, 0x00, 0x00 };
CommonUtil.CalCheckCode(sendData);
byte[] recData = ReadPort(sendData);
if (recData.Length >= 4
&& recData[0] == 0x01
&& recData[1] == 0x02
&& recData[2] == 0x00
&& CommonUtil.ValidCheckCode(recData))
{
switch (recData[3])
{
case 0x00:
msg = "控制主板正在重启";
return false;
case 0x01:
msg = "联机成功";
return true;
case 0x02:
msg = "控制主板正在维护";
return false;
case 0x03:
msg = "控制主板收到的数据格式不正确";
return false;
default:
msg = "未知状态";
return false;
}
}
else if (IsRunning(recData, out msg) || !IsConnected(recData, out msg))
{
return false;
}
else
{
throw new Exception("货机返回的数据格式不正确");
}
}三、如何使用
1、Controller层代码(还不完善，仅测试，真实情况是根据硬件信息，确定调用哪个Dll使用哪个串口)：
#region 创建售货机接口
///
/// 创建售货机接口
///
private IMachine CreateMachine()
{
//return MachineFactory.Create(Request.PhysicalApplicationPath + @"\bin\", "Machine", "COM1");
return MachineFactory.Create(@"D:\售药机代码\Reception\Machine\bin\Debug\", "Machine", "COM1");
}
#endregion
#region 联机
///
/// 联机
///
/// 错误信息
/// 联机是否成功
private bool Connect(out string msg)
{
try
{
IMachine machine = CreateMachine();
DateTime dt1 = DateTime.Now;
while (!machine.Connect(out msg)) //联机
{
if (DateTime.Now.Subtract(dt1).TotalMilliseconds > 20000)
{
msg = "联机超时";
return false;
}
Thread.Sleep(50);
}
return true;
}
catch (Exception ex)
{
msg = ex.Message;
return false;
}
}
#endregion
#region 单次联机
///
/// 单次联机
///
public ActionResult Conn()
{
string msg = null;
Dictionary dic = null;
try
{
IMachine machine = CreateMachine();
if (machine.Connect(out msg)) //联机成功
{
dic = new Dictionary();
dic["ok"] = true;
dic["msg"] = "成功";
return Content(JsonConvert.SerializeObject(dic));
}
else
{
dic = new Dictionary();
dic["ok"] = false;
dic["msg"] = "联机失败：" + msg;
return Content(JsonConvert.SerializeObject(dic));
}
}
catch (Exception ex)
{
dic = new Dictionary();
dic["ok"] = false;
dic["msg"] = "错误：" + ex.Message;
return Content(JsonConvert.SerializeObject(dic));
}
}
#endregion
#region 联机并使能硬纸币器
///
/// 联机并使能硬纸币器
///
public ActionResult ConnectEnable()
{
string msg = null;
Dictionary dic = null;
try
{
IMachine machine = CreateMachine();
if (Connect(out msg) && machine.CoinEnable(out msg) && machine.PaperMoneyEnable(out msg)) //联机并使能硬纸币器成功
{
dic = new Dictionary();
dic["ok"] = true;
dic["msg"] = "成功";
return Content(JsonConvert.SerializeObject(dic));
}
else
{
dic = new Dictionary();
dic["ok"] = false;
dic["msg"] = "硬币器使能失败：" + msg;
return Content(JsonConvert.SerializeObject(dic));
}
}
catch (Exception ex)
{
dic = new Dictionary();
dic["ok"] = false;
dic["msg"] = "错误：" + ex.Message;
return Content(JsonConvert.SerializeObject(dic));
}
}
#endregion 2、前台代码：
@{
ViewBag.Title = "货机接口测试";
Layout = null;
}
@ViewBag.Title