silverlight 操作串口数据的代码
串口PINVOKE代码，需要对超时时间进行设置，如果全为0，则是无限等待。而不是获取不到退出。
public class SerialWrapper : IDisposable
{
#region Enum
public enum StopBits
{
None,
One,
Two,
OnePointFive,
}
public enum Parity
{
None,
Odd,
Even,
Mark,
Space,
}
#endregion
#region Fields
/// <summary>
/// The baud rate at which the communications device operates.
/// </summary>
private readonly int iBaudRate;
/// <summary>
/// The number of bits in the bytes to be transmitted and received.
/// </summary>
private readonly byte byteSize;
/// <summary>
/// The system handle to the serial port connection ('file' handle).
/// </summary>
private IntPtr pHandle = IntPtr.Zero;
/// <summary>
/// The parity scheme to be used.
/// </summary>
private readonly Parity parity;
/// <summary>
/// The name of the serial port to connect to.
/// </summary>
private readonly string sPortName;
/// <summary>
/// The number of bits in the bytes to be transmitted and received.
/// </summary>
private readonly StopBits stopBits;
#endregion
#region Constructor
/// <summary>
/// Creates a new instance of SerialCom.
/// </summary>
/// <param>The name of the serial port to connect to</param>
/// <param>The baud rate at which the communications device operates</param>
/// <param>The number of stop bits to be used</param>
/// <param>The parity scheme to be used</param>
/// <param>The number of bits in the bytes to be transmitted and received</param>
public SerialWrapper(string portName, int baudRate, StopBits stopBits, Parity parity, byte byteSize)
{
if (stopBits == StopBits.None)
throw new ArgumentException("stopBits cannot be StopBits.None", "stopBits");
if (byteSize < 5 || byteSize > 8)
throw new ArgumentOutOfRangeException("The number of data bits must be 5 to 8 bits.", "byteSize");
if (baudRate < 110 || baudRate > 256000)
throw new ArgumentOutOfRangeException("Invalid baud rate specified.", "baudRate");
if ((byteSize == 5 && stopBits == StopBits.Two) || (stopBits == StopBits.OnePointFive && byteSize > 5))
throw new ArgumentException("The use of 5 data bits with 2 stop bits is an invalid combination, " +
"as is 6, 7, or 8 data bits with 1.5 stop bits.");
this.sPortName = portName;
this.iBaudRate = baudRate;
this.byteSize = byteSize;
this.stopBits = stopBits;
this.parity = parity;
}
/// <summary>
/// Creates a new instance of SerialCom.
/// </summary>
/// <param>The name of the serial port to connect to</param>
/// <param>The baud rate at which the communications device operates</param>
/// <param>The number of stop bits to be used</param>
/// <param>The parity scheme to be used</param>
public SerialWrapper(string portName, int baudRate, StopBits stopBits, Parity parity)
: this(portName, baudRate, stopBits, parity, 8)
{
}
#endregion
#region Open
/// <summary>
/// Opens and initializes the serial connection.
/// </summary>
/// <returns>Whether or not the operation succeeded</returns>
public bool Open()
{
pHandle = CreateFile(this.sPortName, FileAccess.ReadWrite, FileShare.None,
IntPtr.Zero, FileMode.Open, 0, IntPtr.Zero);
if (pHandle == IntPtr.Zero) return false;
if (ConfigureSerialPort()) return true;
else
{
Dispose();
return false;
}
}
#endregion
#region Write
/// <summary>
/// Transmits the specified array of bytes.
/// </summary>
/// <param>The bytes to write</param>
/// <returns>The number of bytes written (-1 if error)</returns>
public int Write(byte[] data)
{
FailIfNotConnected();
if (data == null) return 0;
int bytesWritten;
if (WriteFile(pHandle, data, data.Length, out bytesWritten, 0))
return bytesWritten;
return -1;
}
/// <summary>
/// Transmits the specified string.
/// </summary>
/// <param>The string to write</param>
/// <returns>The number of bytes written (-1 if error)</returns>
public int Write(string data)
{
FailIfNotConnected();
// convert the string to bytes
byte[] bytes;
if (data == null)
{
bytes = null;
}
else
{
bytes = Encoding.UTF8.GetBytes(data);
}
return Write(bytes);
}
/// <summary>
/// Transmits the specified string and appends the carriage return to the end
/// if it does not exist.
/// </summary>
/// <remarks>
/// Note that the string must end in '\r\n' before any serial device will interpret the data
/// sent. For ease of programmability, this method should be used instead of Write() when you
/// want to automatically execute the specified command string.
/// </remarks>
/// <param>The string to write</param>
/// <returns>The number of bytes written (-1 if error)</returns>
public int WriteLine(string data)
{
if (data != null && !data.EndsWith("\r\n"))
data += "\r\n";
return Write(data);
}
#endregion
#region Read
/// <summary>
/// Reads any bytes that have been received and writes them to the specified array.
/// </summary>
/// <param>The array to write the read data to</param>
/// <returns>The number of bytes read (-1 if error)</returns>
public int Read(byte[] data)
{
FailIfNotConnected();
if (data == null) return 0;
int bytesRead;
if (ReadFile(pHandle, data, data.Length, out bytesRead, 0))
return bytesRead;
return -1;
}
/// <summary>
/// Reads any data that has been received as a string.
/// </summary>
/// <param>The maximum number of bytes to read</param>
/// <returns>The data received (null if no data)</returns>
public string ReadString(int maxBytesToRead)
{
if (maxBytesToRead < 1) throw new ArgumentOutOfRangeException("maxBytesToRead");
byte[] bytes = new byte[maxBytesToRead];
int numBytes = Read(bytes);
//string data = ASCIIEncoding.ASCII.GetString(bytes, 0, numBytes);
string data = Encoding.UTF8.GetString(bytes, 0, numBytes);
return data;
}
#endregion
#region Dispose Utils
/// <summary>
/// Disconnects and disposes of the SerialCom instance.
/// </summary>
public void Dispose()
{
if (pHandle != IntPtr.Zero)
{
CloseHandle(pHandle);
pHandle = IntPtr.Zero;
}
}
/// <summary>
/// Flushes the serial I/O buffers.
/// </summary>
/// <returns>Whether or not the operation succeeded</returns>
public bool Flush()
{
FailIfNotConnected();
const int PURGE_RXCLEAR = 0x0008; // input buffer
const int PURGE_TXCLEAR = 0x0004; // output buffer
return PurgeComm(pHandle, PURGE_RXCLEAR | PURGE_TXCLEAR);
}
#endregion
#region Private Helpers
/// <summary>
/// Configures the serial device based on the connection parameters pased in by the user.
/// </summary>
/// <returns>Whether or not the operation succeeded</returns>
private bool ConfigureSerialPort()
{
DCB serialConfig = new DCB();
if (GetCommState(pHandle, ref serialConfig))
{
// setup the DCB struct with the serial settings we need
serialConfig.BaudRate = (uint)this.iBaudRate;
serialConfig.ByteSize = this.byteSize;
serialConfig.fBinary = 1; // must be true
serialConfig.fDtrControl = 1; // DTR_CONTROL_ENABLE "Enables the DTR line when the device is opened and leaves it on."
serialConfig.fAbortOnError = 0; // false
serialConfig.fTXContinueOnXoff = 0; // false
serialConfig.fParity = 1; // true so that the Parity member is looked at
switch (this.parity)
{
case Parity.Even:
serialConfig.Parity = 2;
break;
case Parity.Mark:
serialConfig.Parity = 3;
break;
case Parity.Odd:
serialConfig.Parity = 1;
break;
case Parity.Space:
serialConfig.Parity = 4;
break;
case Parity.None:
default:
serialConfig.Parity = 0;
break;
}
switch (this.stopBits)
{
case StopBits.One:
serialConfig.StopBits = 0;
break;
case StopBits.OnePointFive:
serialConfig.StopBits = 1;
break;
case StopBits.Two:
serialConfig.StopBits = 2;
break;
case StopBits.None:
default:
throw new ArgumentException("stopBits cannot be StopBits.None");
}
if (SetCommState(pHandle, ref serialConfig))
{
// 串口连接超时设置
COMMTIMEOUTS timeouts = new COMMTIMEOUTS();
timeouts.ReadIntervalTimeout = 10;
timeouts.ReadTotalTimeoutMultiplier = 10;
timeouts.ReadTotalTimeoutConstant = 10;
timeouts.WriteTotalTimeoutMultiplier = 0;
timeouts.WriteTotalTimeoutConstant = 0;
if (SetCommTimeouts(pHandle, ref timeouts))
{
return true;
}
else
{
return false;
}
}
else
{
return false;
}
}
else
{
return false;
}
}
/// <summary>
/// Helper that throws a InvalidOperationException if we don't have a serial connection.
/// </summary>
private void FailIfNotConnected()
{
if (pHandle == IntPtr.Zero)
throw new InvalidOperationException("You must be connected to the serial port before performing this operation.");
}
#endregion
#region Native Helpers
#region Native structures
/// <summary>
/// Contains the time-out parameters for a communications device.
/// </summary>
[StructLayout(LayoutKind.Sequential)]
struct COMMTIMEOUTS
{
public uint ReadIntervalTimeout;
public uint ReadTotalTimeoutMultiplier;
public uint ReadTotalTimeoutConstant;
public uint WriteTotalTimeoutMultiplier;
public uint WriteTotalTimeoutConstant;
}
/// <summary>
/// Defines the control setting for a serial communications device.
/// </summary>
[StructLayout(LayoutKind.Sequential)]
struct DCB
{
public int DCBlength;
public uint BaudRate;
public uint Flags;
public ushort wReserved;
public ushort XonLim;
public ushort XoffLim;
public byte ByteSize;
public byte Parity;
public byte StopBits;
public sbyte XonChar;
public sbyte XoffChar;
public sbyte ErrorChar;
public sbyte EofChar;
public sbyte EvtChar;
public ushort wReserved1;
public uint fBinary;
public uint fParity;
public uint fOutxCtsFlow;
public uint fOutxDsrFlow;
public uint fDtrControl;
public uint fDsrSensitivity;
public uint fTXContinueOnXoff;
public uint fOutX;
public uint fInX;
public uint fErrorChar;
public uint fNull;
public uint fRtsControl;
public uint fAbortOnError;
}
#endregion
#region Native Methods
// Used to get a handle to the serial port so that we can read/write to it.
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
static extern IntPtr CreateFile(string fileName,
[MarshalAs(UnmanagedType.U4)] FileAccess fileAccess,
[MarshalAs(UnmanagedType.U4)] FileShare fileShare,
IntPtr securityAttributes,
[MarshalAs(UnmanagedType.U4)] FileMode creationDisposition,
int flags,
IntPtr template);
// Used to close the handle to the serial port.
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool CloseHandle(IntPtr hObject);
// Used to get the state of the serial port so that we can configure it.
[DllImport("kernel32.dll")]
static extern bool GetCommState(IntPtr hFile, ref DCB lpDCB);
// Used to configure the serial port.
[DllImport("kernel32.dll")]
static extern bool SetCommState(IntPtr hFile, [In] ref DCB lpDCB);
// Used to set the connection timeouts on our serial connection.
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool SetCommTimeouts(IntPtr hFile, ref COMMTIMEOUTS lpCommTimeouts);
// Used to read bytes from the serial connection.
[DllImport("kernel32.dll")]
static extern bool ReadFile(IntPtr hFile, byte[] lpBuffer,
int nNumberOfBytesToRead, out int lpNumberOfBytesRead, int lpOverlapped);
// Used to write bytes to the serial connection.
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool WriteFile(IntPtr hFile, byte[] lpBuffer,
int nNumberOfBytesToWrite, out int lpNumberOfBytesWritten, int lpOverlapped);
// Used to flush the I/O buffers.
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool PurgeComm(IntPtr hFile, int dwFlags);
#endregion
#endregion
}
调用代码：
serialPort = new SerialWrapper("com8", 14400, SerialWrapper.StopBits.One, SerialWrapper.Parity.None);
serialPort.Open();
string s = serialPort.ReadString(100);
this.ShowMessageBox(s);
serialPort.Dispose();