C# How to place serial input data into a queue and de-que using a backgroundworker

Question

I need to take incoming data from a serial port place the 'ReadExisting' string into a queue, and then de-que back into the user interface.

During the de-que process I will be formatting the incoming string to remove unwanted characters, add LineFeeds (there are no EOL characters in the incoming), etc. and post various parts of the string into several controls (listbox, textbox) for viewing.

This is as far as I have been able to get to create a string (RxString) from incoming data:

 private void serialPort1_DataReceived(object sender,
System.IO.Ports.SerialDataReceivedEventArgs e)     
 {         
 RxString = serialPort1.ReadExisting();         
 this.Invoke(new EventHandler(DisplayText));     
 }

I am able to get the incoming data, but when I try to format it and display it some of the data that comes in gets lost or dropped or something and the text gets unreadable. If I don't format the text & send it straight to a listbox the data is all there, but not useable because of all the extra code characters.

I'd like to handle the (DisplayText) using a backgroundworker so the serial data can come in to a queue so as to not be lost while the backgroundworker handles placing the info on screen. Unless theres a better way.

There is no need to prefix your title with "C#". That's what tags are for. — John Saunders
Very unclear, you didn't post the code that does the actual formatting and thus contains the bug. It is generally pretty important to first assemble the entire response before invoking, ReadExisting() typically only returns one or two characters when you are not debugging. Leverage ReadLine() if you can. — Hans Passant
What is at the end of the serial port? What protocol does it use? — dbasnett
JohnSaunders- thanks It was already one of my tags so didnt know I had to be reundant but added it. makes sense. — user1062142
Hans, its not a bug. it has to do with data coming in faster than the app can format & get back to catch the new incoming data. in any case I think I have solved it. i will be using a QUEUE to catch all incoming data regardless of other events, and then dequeue and format each, FIFO as needed. ReadLine would not work as there is no EOL character being sent- the port never reports an end of line rec'd. — user1062142

NoLifeKing NoLifeKing · Accepted Answer · 2011-11-27T19:02:42

I assume that the data comes one line at the time, so you could always use the Queue-class and use the method Enqueue to add the incoming data.

And to get an item from the Background-worker, just use Dequeue

Here's a link to the MSDN-article about the Queue-class

http://msdn.microsoft.com/en-us/library/7977ey2c.aspx

Example:

private Queue<string> data = new Queue<string>();

private void Rx_GetData(e)
{
    var rxString = e.ReadExisting();
    data.Enqueue(rxString);   
}

private void BackgroundWorker_DoWork()
{
    while(rxConn.IsConnected) // Haven't worked with serial connections, so I don't know the proper property here..
    {
        if(data.Count > 0)
        {
            var str = data.Dequeue();
            FormatString(str);
        }
        Thread.Sleep(10);
    }
}

C# How to place serial input data into a queue and de-que using a backgroundworker

1 Answers