SerialPort類
微軟在.NET中對串口通訊進行了封裝，我們可以在.net2.0及以上版本開發時直接使用SerialPort類對串口進行讀寫操作。
為操作方便，本文對SerialPort類做了一些封裝，暫時取名為SerialPortClient。
SerialPort類的屬性主要包括：
- 串口名稱（PortName）
- 波特率（BaudRate）
- 數據位 DataBits
- 停止位 StopBits
- 奇偶校驗 Parity
SerialPort類的事件主要包括：
- DataReceived：用於異步接收串口數據事件
- ErrorReceived：錯誤處理事件
SerialPort類的方法主要包括：Open();Close();Read();Write()、DiscardInBuffer()、DiscardOutBuffer()等
參數封裝
波特率、數據位這些參數不是系統內置的枚舉類型，為方便實際操作需構造波特率、數據位這兩個枚舉對象。
#region 波特率、數據位的枚舉
/// <summary>
/// 串口數據位列表（5,6,7,8）
/// </summary>
public enum DataBits : int
{
Five = 5,
Six = 6,
Sevent = 7,
Eight = 8
}
/// <summary>
/// 串口波特率列表。
/// 75,110,150,300,600,1200,2400,4800,9600,14400,19200,28800,38400,56000,57600,
/// 115200,128000,230400,256000
/// </summary>
public enum BaudRates : int
{
BR_75 = 75,
BR_110 = 110,
BR_150 = 150,
BR_300 = 300,
BR_600 = 600,
BR_1200 = 1200,
BR_2400 = 2400,
BR_4800 = 4800,
BR_9600 = 9600,
BR_14400 = 14400,
BR_19200 = 19200,
BR_28800 = 28800,
BR_38400 = 38400,
BR_56000 = 56000,
BR_57600 = 57600,
BR_115200 = 115200,
BR_128000 = 128000,
BR_230400 = 230400,
BR_256000 = 256000
}
#endregion
控件操作封裝
對常用的參數下拉列表綁定做一個封裝，該操作為封裝類的靜態方法。
為兼容第三方控件使用IList接口，不直接使用ComboBox類型作為參數。
#region 靜態方法
/// <summary>
/// 設置串口號
/// </summary>
/// <param name="obj">需要綁定的項的集合（如：ComboBox中項的集合ComboBox.Items）</param>
public static void SetPortNameValues(IList obj)
{
obj.Clear();
try
{
foreach (string str in SerialPort.GetPortNames())
{
obj.Add(str);
}
}
catch (Exception e)
{
Console.WriteLine("未能查詢到串口名稱——"+e.ToString());
}
}
/// <summary>
/// 設置波特率
/// </summary>
/// <param name="obj">需要綁定的項的集合（如：ComboBox中項的集合ComboBox.Items）</param>
public static void SetBauRateValues(IList obj)
{
obj.Clear();
foreach (BaudRates rate in Enum.GetValues(typeof(BaudRates)))
{
obj.Add(((int)rate).ToString());
}
}
/// <summary>
/// 設置數據位
/// </summary>
/// <param name="obj">需要綁定的項的集合（如：ComboBox中項的集合ComboBox.Items）</param>
public static void SetDataBitsValues(IList obj)
{
obj.Clear();
foreach (DataBits databit in Enum.GetValues(typeof(DataBits)))
{
obj.Add(((int)databit).ToString());
}
}
/// <summary>
/// 設置校驗位列表
/// </summary>
/// <param name="obj">需要綁定的項的集合（如：ComboBox中項的集合ComboBox.Items）</param>
public static void SetParityValues(IList obj)
{
obj.Clear();
foreach (string str in Enum.GetNames(typeof(Parity)))
{
obj.Add(str);
}
}
/// <summary>
/// 設置停止位
/// </summary>
/// <param name="obj">需要綁定的項的集合（如：ComboBox中項的集合ComboBox.Items）</param>
public static void SetStopBitValues(IList obj)
{
obj.Clear();
foreach (string str in Enum.GetNames(typeof(StopBits)))
{
obj.Add(str);
}
}
#endregion
SerialPortClient類實現
該部分代碼是SerialPortClient類非靜態操作部分的實現，完整的類實現需要加上上面的控件操作封裝的實現代碼，具體請參照Demo源碼。
#region 變量屬性
public event Action<List<byte>> DataReceived;
public event SerialErrorReceivedEventHandler ErrorReceived;
private SerialPort comPort = new SerialPort();
private string portName = "COM1";//串口號，默認COM1
private BaudRates baudRate = BaudRates.BR_9600;//波特率
private Parity parity = Parity.None;//校驗位
private StopBits stopBits = StopBits.One;//停止位
private DataBits dataBits = DataBits.Eight;//數據位
/// <summary>
/// 串口號
/// </summary>
public string PortName
{
get { return portName; }
set { portName = value; }
}
/// <summary>
/// 波特率
/// </summary>
public BaudRates BaudRate
{
get { return baudRate; }
set { baudRate = value; }
}
/// <summary>
/// 奇偶校驗位
/// </summary>
public Parity Parity
{
get { return parity; }
set { parity = value; }
}
/// <summary>
/// 數據位
/// </summary>
public DataBits DataBits
{
get { return dataBits; }
set { dataBits = value; }
}
/// <summary>
/// 停止位
/// </summary>
public StopBits StopBits
{
get { return stopBits; }
set { stopBits = value; }
}
#endregion
#region 構造函數
/// <summary>
/// 無參構造函數
/// </summary>
public SerialPortClient()
{
BoundEvents();
}
void BoundEvents()
{
comPort.DataReceived += new SerialDataReceivedEventHandler(comPort_DataReceived);
comPort.ErrorReceived += new SerialErrorReceivedEventHandler(comPort_ErrorReceived);
}
/// <summary>
/// 參數構造函數（使用枚舉參數構造）
/// </summary>
/// <param name="baud">波特率</param>
/// <param name="par">奇偶校驗位</param>
/// <param name="sBits">停止位</param>
/// <param name="dBits">數據位</param>
/// <param name="name">串口號</param>
public SerialPortClient(string name, BaudRates baud, Parity par, DataBits dBits, StopBits sBits)
{
this.portName = name;
this.baudRate = baud;
this.parity = par;
this.dataBits = dBits;
this.stopBits = sBits;
BoundEvents();
}
/// <summary>
/// 參數構造函數（使用字符串參數構造）
/// </summary>
/// <param name="baud">波特率</param>
/// <param name="par">奇偶校驗位</param>
/// <param name="sBits">停止位</param>
/// <param name="dBits">數據位</param>
/// <param name="name">串口號</param>
public SerialPortClient(string name, string baud, string par, string dBits, string sBits)
{
this.portName = name;
this.baudRate = (BaudRates)Enum.Parse(typeof(BaudRates), baud);
this.parity = (Parity)Enum.Parse(typeof(Parity), par);
this.dataBits = (DataBits)Enum.Parse(typeof(DataBits), dBits);
this.stopBits = (StopBits)Enum.Parse(typeof(StopBits), sBits);
BoundEvents();
}
#endregion
#region 事件處理函數
/// <summary>
/// 數據倉庫
/// </summary>
List<byte> datapool = new List<byte>();//存放接收的所有字節
/// <summary>
/// 數據接收處理
/// </summary>
void comPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
if (comPort.IsOpen) //判斷是否打開串口
{
Byte[] receivedData = new Byte[comPort.BytesToRead]; //創建接收字節數組
comPort.Read(receivedData, 0, receivedData.Length); //讀取數據
//觸發整條記錄的處理
if (DataReceived != null)
{
datapool.AddRange(receivedData);
DataReceived(datapool);
}
}
else
{
Console.WriteLine("請打開某個串口", "Error");
}
}
/// <summary>
/// 錯誤處理函數
/// </summary>
void comPort_ErrorReceived(object sender, SerialErrorReceivedEventArgs e)
{
if (ErrorReceived != null)
{
ErrorReceived(sender, e);
}
}
#endregion
#region 串口關閉/打開
/// <summary>
/// 端口是否已經打開
/// </summary>
public bool IsOpen
{
get
{
return comPort.IsOpen;
}
}
/// <summary>
/// 打開端口
/// </summary>
/// <returns></returns>
public void Open()
{
if (comPort.IsOpen) comPort.Close();
comPort.PortName = portName;
comPort.BaudRate = (int)baudRate;
comPort.Parity = parity;
comPort.DataBits = (int)dataBits;
comPort.StopBits = stopBits;
comPort.Open();
}
/// <summary>
/// 關閉端口
/// </summary>
public void Close()
{
if (comPort.IsOpen) comPort.Close();
}
/// <summary>
/// 丟棄來自串行驅動程序的接收和發送緩沖區的數據
/// </summary>
public void DiscardBuffer()
{
comPort.DiscardInBuffer();
comPort.DiscardOutBuffer();
}
#endregion
#region 寫入數據
/// <summary>
/// 寫入數據
/// </summary>
/// <param name="buffer"></param>
public void Write(byte[] buffer, int offset, int count)
{
if (!(comPort.IsOpen)) comPort.Open();
comPort.Write(buffer,offset, count);
}
/// <summary>
/// 寫入數據
/// </summary>
/// <param name="buffer">寫入端口的字節數組</param>
public void Write(byte[] buffer)
{
if (!(comPort.IsOpen)) comPort.Open();
comPort.Write(buffer, 0, buffer.Length);
}
#endregion
SerialPortClient類使用
SerialPortClient類使用很簡單，主要分為初始化下拉列表、初始化串口（綁定數據接收、錯誤處理事件）兩步，在窗體加載事件中調用即可。代碼如下：
//全局變量
SerialPortClient portClient = new SerialPortClient();
private void InitPort()
{
portClient.DataReceived+=new Action<List<byte>>(datapool=>
{
//匹配數據幀，此處以0xea 0xeb為幀頭、0xfa 0xfb為幀尾
//實際通訊協議應該更復雜
while (true)
{
if (datapool.Count <4) break;
if ((datapool[0] == 0xea) && (datapool[0] == 0xeb))
{
datapool.RemoveAt(0);
continue;
}
int index = -1;//正確作法是記住上次最末尾的索引，避免重復匹配
for (int i = 0; i < datapool.Count-1; i++)
{
if (datapool[i] == 0xfa && datapool[i + 1] == 0xfb)
{
index = i;
break;
}
}
if (index != -1)
{
byte[] data = datapool.GetRange(0, index + 2).ToArray();
datapool.RemoveRange(0, index + 2);
string msg = Encoding.UTF8.GetString(data,2,data.Length-4);
this.BeginInvoke(new Action(() => { textBox_Recive.Text = msg; }));
}
else break;
}
});
}
private void InitCmb()
{
//綁定端口號
SerialPortClient.SetPortNameValues(comboBox_Com.Items);
comboBox_Com.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox_Com.SelectedIndexChanged += new EventHandler((obj, e) =>
{
if (comboBox_Com.SelectedItem!=null)
{
portClient.PortName = comboBox_Com.SelectedItem.ToString();
}
});
comboBox_Com.SelectedIndex = 0;
//波特率
SerialPortClient.SetBauRateValues(comboBox_BaudRates.Items);
comboBox_BaudRates.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox_BaudRates.SelectedIndexChanged += new EventHandler((obj, e) =>
{
if (comboBox_BaudRates.SelectedItem != null)
{
portClient.BaudRate = (BaudRates)Enum.Parse(typeof(BaudRates), comboBox_BaudRates.SelectedItem.ToString());
}
});
comboBox_BaudRates.SelectedIndex = 9;
//數據位
SerialPortClient.SetDataBitsValues(comboBox_DataBits.Items);
comboBox_DataBits.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox_DataBits.SelectedIndexChanged += new EventHandler((obj, e) =>
{
if (comboBox_DataBits.SelectedItem != null)
{
portClient.DataBits = (DataBits)Enum.Parse(typeof(DataBits), comboBox_DataBits.SelectedItem.ToString());
}
});
comboBox_DataBits.SelectedIndex = 3;
//校驗位
SerialPortClient.SetParityValues(comboBox_Parity.Items);
comboBox_Parity.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox_Parity.SelectedIndexChanged += new EventHandler((obj, e) =>
{
if (comboBox_Parity.SelectedItem != null)
{
portClient.Parity = (Parity)Enum.Parse(typeof(Parity), comboBox_Parity.SelectedItem.ToString());
}
});
comboBox_Parity.SelectedIndex = 0;
//停止位
SerialPortClient.SetStopBitValues(comboBox_StopBits.Items);
comboBox_StopBits.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox_StopBits.SelectedIndexChanged += new EventHandler((obj, e) =>
{
if (comboBox_StopBits.SelectedItem != null)
{
portClient.StopBits = (StopBits)Enum.Parse(typeof(StopBits), comboBox_StopBits.SelectedItem.ToString());
}
});
comboBox_StopBits.SelectedIndex = 1;
}
串口的打開、關閉、狀態顯示等操作請查看文章末尾的Demo源碼。
測試Demo
Demo下載：https://files-cdn.cnblogs.com/files/timefiles/SerialPortDemo.rar