public PortStatus IsPortAvailable(string s)
{
IntPtr hObject = Win32Com.CreateFile(s, 0xc0000000, 0, IntPtr.Zero, 3, 0x40000000, IntPtr.Zero);
if (hObject == ((IntPtr)(-1)))
{
if (Marshal.GetLastWin32Error() == 5L)
{
return(PortStatus.unavailable);
}
hObject = Win32Com.CreateFile(this.AltName(s), 0xc0000000, 0, IntPtr.Zero, 3, 0x40000000, IntPtr.Zero);
if (hObject == ((IntPtr)(-1)))
{
if (Marshal.GetLastWin32Error() == 5L)
{
return(PortStatus.unavailable);
}
return(PortStatus.absent);
}
}
Win32Com.CloseHandle(hObject);
return(PortStatus.available);
}
public bool Open()
{
Win32Com.DCB lpDCB = new Win32Com.DCB();
Win32Com.COMMTIMEOUTS lpCommTimeouts = new Win32Com.COMMTIMEOUTS();
Win32Com.OVERLAPPED structure = new Win32Com.OVERLAPPED();
if (!this.online)
{
CommBaseSettings settings = this.CommSettings();
this.hPort = Win32Com.CreateFile(settings.port, 0xc0000000, 0, IntPtr.Zero, 3, 0x40000000, IntPtr.Zero);
if (this.hPort == ((IntPtr)(-1)))
{
if (Marshal.GetLastWin32Error() == 5L)
{
return(false);
}
this.hPort = Win32Com.CreateFile(this.AltName(settings.port), 0xc0000000, 0, IntPtr.Zero, 3, 0x40000000, IntPtr.Zero);
if (this.hPort == ((IntPtr)(-1)))
{
if (Marshal.GetLastWin32Error() != 5L)
{
throw new CommPortException("Port Open Failure");
}
return(false);
}
}
this.online = true;
lpCommTimeouts.ReadIntervalTimeout = uint.MaxValue;
lpCommTimeouts.ReadTotalTimeoutConstant = 0;
lpCommTimeouts.ReadTotalTimeoutMultiplier = 0;
if (settings.sendTimeoutMultiplier == 0)
{
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
{
lpCommTimeouts.WriteTotalTimeoutMultiplier = 0;
}
else
{
lpCommTimeouts.WriteTotalTimeoutMultiplier = 0x2710;
}
}
else
{
lpCommTimeouts.WriteTotalTimeoutMultiplier = settings.sendTimeoutMultiplier;
}
lpCommTimeouts.WriteTotalTimeoutConstant = settings.sendTimeoutConstant;
lpDCB.init((settings.parity == Parity.odd) || (settings.parity == Parity.even), settings.txFlowCTS, settings.txFlowDSR, (int)settings.useDTR, settings.rxGateDSR, !settings.txWhenRxXoff, settings.txFlowX, settings.rxFlowX, (int)settings.useRTS);
lpDCB.BaudRate = settings.baudRate;
lpDCB.ByteSize = (byte)settings.dataBits;
lpDCB.Parity = (byte)settings.parity;
lpDCB.StopBits = (byte)settings.stopBits;
lpDCB.XoffChar = (byte)settings.XoffChar;
lpDCB.XonChar = (byte)settings.XonChar;
if (((settings.rxQueue != 0) || (settings.txQueue != 0)) && !Win32Com.SetupComm(this.hPort, (uint)settings.rxQueue, (uint)settings.txQueue))
{
this.ThrowException("Bad queue settings");
}
if ((settings.rxLowWater == 0) || (settings.rxHighWater == 0))
{
Win32Com.COMMPROP commprop;
if (!Win32Com.GetCommProperties(this.hPort, out commprop))
{
commprop.dwCurrentRxQueue = 0;
}
if (commprop.dwCurrentRxQueue > 0)
{
lpDCB.XoffLim = lpDCB.XonLim = (short)(commprop.dwCurrentRxQueue / 10);
}
else
{
lpDCB.XoffLim = (short)(lpDCB.XonLim = 8);
}
}
else
{
lpDCB.XoffLim = (short)settings.rxHighWater;
lpDCB.XonLim = (short)settings.rxLowWater;
}
if (!Win32Com.SetCommState(this.hPort, ref lpDCB))
{
this.ThrowException("Bad com settings");
}
if (!Win32Com.SetCommTimeouts(this.hPort, ref lpCommTimeouts))
{
this.ThrowException("Bad timeout settings");
}
this.stateBRK = 0;
if (settings.useDTR == HSOutput.none)
{
this.stateDTR = 0;
}
if (settings.useDTR == HSOutput.online)
{
this.stateDTR = 1;
}
if (settings.useRTS == HSOutput.none)
{
this.stateRTS = 0;
}
if (settings.useRTS == HSOutput.online)
{
this.stateRTS = 1;
}
this.checkSends = settings.checkAllSends;
structure.Offset = 0;
structure.OffsetHigh = 0;
if (this.checkSends)
{
structure.hEvent = this.writeEvent.Handle;
}
else
{
structure.hEvent = IntPtr.Zero;
}
this.ptrUWO = Marshal.AllocHGlobal(Marshal.SizeOf(structure));
Marshal.StructureToPtr(structure, this.ptrUWO, true);
this.writeCount = 0;
this.empty[0] = true;
this.dataQueued = false;
this.rxException = null;
this.rxExceptionReported = false;
this.rxThread = new Thread(new ThreadStart(this.ReceiveThread));//打开串口的同时也打开了接收线程
this.rxThread.Name = "CommBaseRx";
this.rxThread.Priority = ThreadPriority.AboveNormal;
this.rxThread.Start();
this.startEvent.WaitOne(500, false);
this.auto = false;
if (this.AfterOpen())
{
this.auto = settings.autoReopen;
return(true);
}
this.Close();
}
return(false);
}