问题
I am trying to read data from an RS-232 port. Does anyone have an example of how I get the data from the port/buffer and make sure that I have all the data as it can be multiline data.
Do I simply read it as follows ?
string Rxstring = port.ReadLine();
Console.WriteLine(Rxstring);
回答1:
Try this:
using System.IO.Ports;
...
private SerialPort port = new SerialPort("COM1", 9600, Parity.None, 8, StopBits.One);
Console.WriteLine(port.ReadExisting());
Details can be found at Coad's Code.
回答2:
Q: how to get the date from the port/buffer, or input data from your connected device. AND make sure that you have all the data.
A: i have worked extensively with .net serial port class drivers where i was tasked to create reliable, robust code. this means that a connected device under test has to run and NOT fail over a LONG period of time. Serial port can AND does lose data! don't forget that.
//from top of the head;
using System.Port.IO;
using System.Port;
private class mywindowsForm: Form
{
StringBuilder sbReceived = new StringBuilder();
string Received = string.Empty;
int byteCOUNT = 0;
System.Windows.Timers.Timer serialTimer;
//Default constructor
myWindowsForm()
{
//assume that you clicked and dragged serial port in
serialPort1 = new SerialPort();//create new serial port instance
serialPort1.Baud = 9600;
serialPort1.DataReceived+=<Tab><Enter>
//serial port timer
serialTimer = new System.Windows.Timers.Timer(500);//set to 500ms time delay
serialTimer.Elapsed+=<TAB><ENTER>
}
void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
//serial port has detected input data
//however, we only want to get serial data so,
if(e.EventType !=SerialData.Chars) return;
//good design practice dictates that we have an event handler that we invoke
this.BeginInvoke(new eventhandler(AddReceive));//beginInvoke is designed to deal with asynchronous processes like serial port data.
}
private void AddReceive(object s, EventArg e)
{
byteCOUNT=serialPort1.BytesToRead;//count the number of bytes in RX buffer
if(byteCOUNT > 0)
{
string ST = serialPort1.ReadTo("\n");//lets get one line at a time
sbReceived.Append(ST);//add whatever has been RX'd to our container.
serialPort1.Interval =100;
serialPort1.Start();//to be sure we have all data, check to see for stragglers.
}
}
void serialTimer(object Sender, TimerElapsedEventArgs e)
{
serialTimer.Stop();
this.BeginInvoke(new EventHandler(ReadData));
}
void ReadData(object Sender, EventArgs e)
{
//parse output for required data and output to terminal display (build one using rich text box)
Received = sbReceived.ToString();
//and if we have ANY MORE incoming data left over in serial buffer
if(Received.Length > 0)
{
//your data
}
}
}
this should be plenty to get you started. this is result of years of creating customized terminal emulators in c#. there are other things that can be done, particularly if you have large amount of i/o data you need to set up handshaking with device. you have to let the device handle at a rate that the device is happy with. in cases where larger data has to be transferred consider setting up a simple packet passing protocol and command semaphore construct - or use a protocol as defined that the controller / device is designed to work with.
来源:https://stackoverflow.com/questions/1379044/c-sharp-readin-from-serial-port-buffer