我們知道對於
標准DLL,可以采用DllImport進行調用。例如：
[DllImport("KMY350X.dll")]
private static extern int OpenPort(int PortNum, int BaudRate);
如果一些廠家比較懶的話，沒有提供相應的dll,我們只能對它進行串口通信編程了。以前從沒接觸過串口編程，最近在一個項目中有幾個地方都需要采用串口通信，跟公司一個老手請教後，感覺學到了很多東西，特在此做個總結:
一：首先我們來認識下什麼是串口：
右鍵 我的電腦-管理-設備管理器-端口，選擇一個端口，點擊屬性。
我們可以看到該串口的屬性，在C#中我們使用SerialPort類來表示串口
ConfigClass config = new ConfigClass();
comm.serialPort.PortName = config.ReadConfig("SendHealCard");
//波特率
comm.serialPort.BaudRate = 9600;
//數據位
comm.serialPort.DataBits = 8;
//兩個停止位
comm.serialPort.StopBits = System.IO.Ports.StopBits.One;
//無奇偶校驗位
comm.serialPort.Parity = System.IO.Ports.Parity.None;
comm.serialPort.ReadTimeout = 100;
comm.serialPort.WriteTimeout = -1;
二：串口調試工具：
在對串口進行編程時候，我們要向串口發送指令，然後我們解析串口返回的指令。在這裡向大家推薦一款工具。
串口調試助手.exe
將要發送的指令用空格隔開，選擇HEX顯示為放回的字符串。
三：正式編程：
編寫Comm類:
public class Comm
{
public delegate void EventHandle(byte[] readBuffer);
public event EventHandle DataReceived;
public SerialPort serialPort;
Thread thread;
volatile bool _keepReading;
public Comm()
{
serialPort = new SerialPort();
thread = null;
_keepReading = false;
}
public bool IsOpen
{
get
{
return serialPort.IsOpen;
}
}
private void StartReading()
{
if (!_keepReading)
{
_keepReading = true;
thread = new Thread(new ThreadStart(ReadPort));
thread.Start();
}
}
private void StopReading()
{
if (_keepReading)
{
_keepReading = false;
thread.Join();
thread = null;
}
}
private void ReadPort()
{
while (_keepReading)
{
if (serialPort.IsOpen)
{
int count = serialPort.BytesToRead;
if (count > 0)
{
byte[] readBuffer = new byte[count];
try
{
Application.DoEvents();
serialPort.Read(readBuffer, 0, count);
if(DataReceived != null)
DataReceived(readBuffer);
Thread.Sleep(100);
}
catch (TimeoutException)
{
}
}
}
}
}
public void Open()
{
Close();
serialPort.Open();
if (serialPort.IsOpen)
{
StartReading();
}
else
{
MessageBox.Show("串口打開失敗！");
}
}
public void Close()
{
StopReading();
serialPort.Close();
}
public void WritePort(byte[] send, int offSet, int count)
{
if (IsOpen)
{
serialPort.Write(send, offSet, count);
}
}
}
注冊串口：
Comm
comm = new Comm();
ConfigClass config = new ConfigClass();
comm.serialPort.PortName = config.ReadConfig("SendHealCard");
//波特率
comm.serialPort.BaudRate = 9600;
//數據位
comm.serialPort.DataBits = 8;
//兩個停止位
comm.serialPort.StopBits = System.IO.Ports.StopBits.One;
//無奇偶校驗位
comm.serialPort.Parity = System.IO.Ports.Parity.None;
comm.serialPort.ReadTimeout = 100;
comm.serialPort.WriteTimeout = -1;
comm.Open();
if (comm.IsOpen)
{
comm.DataReceived += new Comm.EventHandle(comm_DataReceived);
}
發送指令：
/// <summary>
/// 發卡到機口
/// </summary>
private void SendCardToOut()
{
is_read_card = false;
sendCardToOut = true;
byte[] send = { 0x02, 0x46, 0x43, 0x34, 0x03, 0x30 };
if (comm.IsOpen)
{
comm.WritePort(send, 0, send.Length);
}
}
收到指令，並解析：
void comm_DataReceived(byte[] readBuffer1)
{
//log.Info(HexCon.ByteToString(readBuffer));
if (readBuffer1.Length == 1)
{
receive = HealCardClass.ByteToString(readBuffer1);
string str = "06";
if (string.Equals(receive.Trim(), str, StringComparison.CurrentCultureIgnoreCase))
{
try
{
if (is_read_card)
{
byte[] send = new byte[1];
send[0] = 0x05;
comm.WritePort(send, 0, send.Length);
Thread.Sleep(500);
comm.DataReceived -= new Comm.EventHandle(comm_DataReceived);
InitReadComm();
}
if (sendCardToOut)
{
byte[] send = new byte[1];
send[0] = 0x05;
comm.WritePort(send, 0, send.Length);
readComm.DataReceived -= new Comm.EventHandle(readComm_DataReceived);
readComm.Close();
log.Info("發卡完成！");
lblMsg.Text = "發卡成功！";
lblSendCardMsg.Text = "發卡完成，請收好卡！";
timer1.Tick -= new EventHandler(timer1_Tick);
PlaySound();
this.btnOK.Enabled = true;
}
}
catch (Exception ex)
{
log.Info(ex.ToString());
}
}
}
}
至此，串口通信編程告一段落
