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How to correctly parse received serial data into lines?

I'm creating a program which communicates with a serial device which is constantly sending data. I'm reading data from device every 100ms (using a timer). I use port.ReadExisting() to receive all currently available data from the device then I try split it into lines, because I need to check some of the received data and the best way is to check lines. The problem occurs when device sends data which doesn't end with "\r\n" or '\n'.
In a perfect situation port.ReadExisting() returns: "sampletext\r\nsomesampletext\nsampletext\r\n
But a problem occurs when there's no CR or LF character at the end:
First time port.ReadExisting() returns this: "text\nsamp"
Second time port.ReadExisting() returns this: letext\r\ntext\r\n"
End result should look like this:
text
sampletext
text
But what I get looks like this:
text
samp
letext
text
My code:
This is the timer which runs every 100ms:
private void CommandTimer_Tick(object sender, EventArgs e)
{
BackgroundWorker seriaDataWorker = new BackgroundWorker();
seriaDataWorker.DoWork += (obj, p) => PrintSerialData();
seriaDataWorker.RunWorkerAsync();
}
BackgroundWorker which gets called by the timer:
private void PrintSerialData()
{
try
{
if (RandomReboot)
{
RebootWatch.Start();
}
if (COMport.IsOpen)
{
if (COMport.BytesToRead != 0)
{
SerialPrint(COMport.ReadExisting());
}
}
}
catch (System.IO.IOException SerialException)
{
return;
}
}
Function which parses received data into lines:
private void SerialPrint(string data)
{
using (var buffer = new StringReader(data))
{
string line = "";
while((line = buffer.ReadLine()) != null)
{
if (CheckForAnsw)
{
ReceivedCommandData = line;
if (ReceivedCommandData.Contains(AnswExpected))
{
ReceivedAnsw = true;
ReceivedLine = ReceivedCommandData;
ReceivedCommandData = "";
}
}
this.Invoke(new MethodInvoker(delegate
{
AppendText(TextBox_System_Log, Color.Black, line + "\r\n");
}
));
}
}
}
I know that the problem is that buffer.ReadLine() treats remainder of the string which doesn't end with a CR or LF character as a seperate line but I don't know how to fix it.
I tried using port.ReadLine() in the past but it is way slower and causes problems for me when serial ports get disconnected etc.

I don't think there's an easy way to handle this with the StringReader. Instead, you can split the string yourself:
private static string _buffer = string.Empty;
private static void SerialPrint(string data)
{
// Append the new data to the leftover of the previous operation
data = _buffer + data;
int index = data.IndexOf('\n');
int start = 0;
while (index != -1)
{
var command = data.Substring(start, index - start);
ProcessCommand(command.TrimEnd('\r'));
start = index + 1;
index = data.IndexOf('\n', start);
}
// Store the leftover in the buffer
if (!data.EndsWith("\n"))
{
_buffer = data.Substring(start);
}
else
{
_buffer = string.Empty;
}
}
private static void ProcessCommand(string command)
{
Console.WriteLine(command);
}

You can use AnonymousPipes to transport and buffer the incoming data and read them as lines to output them to somewhere.
Here is a little example which creates a server and client pipe stream, then writes data to the server in one task (with some newline in the data) and reads the data in a different task per line and outputs them to the console.
public class Program
{
public static async Task Main()
{
(var writer, var reader) = CreatePipe();
using (writer)
using (reader)
{
var writerTask = Task.Run(async () =>
{
writer.AutoFlush = true;
writer.Write("?");
for (int i = 0; i < 100; i++)
{
if (i % 10 == 9)
{
await writer.WriteAsync("!");
await writer.WriteAsync(Environment.NewLine);
await writer.WriteAsync("?");
}
else
{
await writer.WriteAsync((i % 10).ToString());
}
await Task.Delay(100);
}
writer.Close();
});
var readerTask = Task.Run(async () =>
{
while (!reader.EndOfStream)
{
var line = await reader.ReadLineAsync();
Console.WriteLine(line);
}
});
await Task.WhenAll(writerTask, readerTask);
}
}
public static (StreamWriter, StreamReader) CreatePipe()
{
var server = new AnonymousPipeServerStream(PipeDirection.Out);
var client = new AnonymousPipeClientStream(server.GetClientHandleAsString());
return
(
new StreamWriter(server, Encoding.UTF8),
new StreamReader(client, Encoding.UTF8)
);
}
}
Try to adapt this code to your use case and comment if there are difficulies.

Your issue with \r\n and \n can be covered by using Environment.NewLine. I'm not sure what AppendText does, but if you're using it to store the values, then you're overdoing it. What you need is to store all data first in a StringBuilder then process them, OR process each data and store them in managed type such as Array, to define each line separately. Only use the string in the presentation layer (if you have some GUI that you want the user to see the results).
So, what I suggest is to store the lines in StringBuilder Something like this :
private readonly StringBuilder _strDataBuilder = new StringBuilder();
private void PrintSerialData()
{
try
{
if (RandomReboot)
{
RebootWatch.Start();
}
if(COMport.IsOpen && COMport.BytesToRead != 0)
{
var data = COMport.ReadExisting();
if(!string.IsNullOrEmpty(data)) {
_strDataBuilder.Append(data);
}
}
}
catch (System.IO.IOException SerialException)
{
return;
}
}
private void SerialPrint()
{
var data = _strDataBuilder.ToString();
if(string.IsNullOrEmpty(data)) { return; }
var lines = data.Split(Environment.NewLine);
if(lines.Length == 0) { return; }
for(int x = 0; x < lines.Length; x++)
{
var line = lines[x];
if (CheckForAnsw)
{
ReceivedCommandData = line;
if (ReceivedCommandData.Contains(AnswExpected))
{
ReceivedAnsw = true;
ReceivedLine = ReceivedCommandData;
ReceivedCommandData = "";
}
}
this.Invoke(new MethodInvoker(delegate
{
AppendText(TextBox_System_Log, Color.Black, line + Environment.NewLine);
}
));
}
}
Storing them first would make things more maintainability and fixability when you want to add more processing steps or reuse the results.
Although the SerialPrint() is unnessary if you just re-print the data in the GUI. As the data already separated in lines. So, if you do
TextBox_System_Log.Text = _strDataBuilder.ToString();
Directly, would list them in lines in the default color. However, if you intended to split them to process each line separately (to validate for instance), then it would be okay.

You can try like below code:
public void DataReceivedSerialPort(object sender, SerialDataReceivedEventArgs e)
{
readExistingData = "";
SerialPort sp = (SerialPort)sender;
sp.ReadTimeout = 100;
do
{
readExistingData = "";
try
{
readExistingData = sp.ReadLine();
if (readExistingData == "")
{
readExistingData = sp.ReadLine();
}
dataReadFromSerialPort += readExistingData;
}
catch
{
try
{
readExistingData = sp.ReadExisting();
dataReadFromSerialPort += readExistingData + "\r\n";
}
catch { }
}
UI.insert_new_items_into_textBoxUARTLog(readExistingData);
} while (readExistingData != "");
}

Why value does not fall within the expected range when setting Value Changed for Gatt Characteristic

I would like to keep on reading characteristic/set value changed event handlers for characteristics from my BLE 4.0 device, by using the ValueChanged callback in Universal Windows Platform C# in Visual Studio 2017.
I followed some tutorial from these sites: Damian Blog's Windows Universal with BLE, Bluetooth Gatt's Git Hub, Bluetooth Generic Attribute Profile - Heart Rate Service and Dr. Jukka's mobile Blog on BLE. All of them are using ValueChanged and I have tried to follow what they did.
Unfortunately, instead of ValueChanged being triggered, I receive the following error when using the ValueChanged callback.
System.ArgumentException: 'Value does not fall within the expected range.'
This line of code is producing the error:
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
Here is more details of my source code:
NOTE: I am using COM 7 for my dongler and my program could discover the BLE's device name, and could discover the Uuid of the services and characteristics.
public List<string> serviceList = new List<string>();
public List<string> characteristicList = new List<string>();
public BluetoothLEDevice myDevice { get; set; }
public MainPage()
{
this.InitializeComponent();
}
private async void Page_Loaded(object sender, RoutedEventArgs e)
{
// Find the com port
string selector = SerialDevice.GetDeviceSelector("COM7");
DeviceInformationCollection devices = await DeviceInformation.FindAllAsync(selector);
if (devices.Count > 0)
{
var dialog = new MessageDialog("Com Device found");
await dialog.ShowAsync();
DeviceInformation deviceInfo = devices[0];
SerialDevice serialDevice = await SerialDevice.FromIdAsync(deviceInfo.Id);
serialDevice.BaudRate = 9600;
serialDevice.DataBits = 8;
serialDevice.StopBits = SerialStopBitCount.One;
serialDevice.Parity = SerialParity.None;
}
else
{
MessageDialog popup = new MessageDialog("Sorry, no device found.");
await popup.ShowAsync();
}
// After com port is found, search for device
foreach (DeviceInformation di in await DeviceInformation.FindAllAsync(BluetoothLEDevice.GetDeviceSelector()))
{
BluetoothLEDevice bleDevice = await BluetoothLEDevice.FromIdAsync(di.Id);
// Display BLE device name
var dialogBleDeviceName = new MessageDialog("BLE Device Name " + bleDevice.Name);
await dialogBleDeviceName.ShowAsync();
myDevice = bleDevice;
}
// Check device connection
myDevice.ConnectionStatusChanged += OnConnectionStatusChanged;
foreach (var service in myDevice.GattServices)
{
serviceList.Add(service.Uuid.ToString());
// Verify if service is discovered by displaying a popup
MessageDialog serviceUuidPopUp = new MessageDialog("Adding Service Uuid to list " + service.Uuid.ToString() );
await serviceUuidPopUp.ShowAsync();
foreach (var characteristic in service.GetAllCharacteristics())
{
var characteristicUuid = characteristic.Uuid.ToString().ToLowerInvariant();
characteristicList.Add(characteristicUuid);
// Verify if characteristic is discovered by displaying a popup
MessageDialog charUuidPopUp = new MessageDialog("Adding characteristic Uuid to list " + characteristicUuid);
await charUuidPopUp.ShowAsync();
// set value changed event handlers for characteristics
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
}
}
}
private void OnConnectionStatusChanged(BluetoothLEDevice sender, object args)
{
if (sender.ConnectionStatus == BluetoothConnectionStatus.Connected)
{
System.Diagnostics.Debug.WriteLine("Connected");
}
else
{
System.Diagnostics.Debug.WriteLine("Disconnected");
}
}
private void Oncharacteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
{
byte[] data = new byte[args.CharacteristicValue.Length];
DataReader.FromBuffer(
args.CharacteristicValue).ReadBytes(data);
string text = Encoding.UTF8.GetString(data, 0, data.Length);
}
UPDATE 1
I tried to check Characteristic Properties before set value changed event handlers for my characteristics by following the answer given by rudi belt on SO.
if (characteristic.CharacteristicProperties == (GattCharacteristicProperties.Read | GattCharacteristicProperties.Notify))
{
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
}
Unfortunately, this IF statement is not executed.
UPDATE 2
I have tried to remove ALL the codes inside Oncharacteristic_ValueChanged method. But it still gives me the same error
System.ArgumentException: 'Value does not fall within the expected range.'
I have been spending a lot of time trying to solve this problem. I will be very happy if anyone can help me on this. Thank you!

Reading your efforts in the former question I can provide a working example, but first some explanation.
myDevice.ConnectionStatusChanged is not needed, it is only used to notice a connection is lost or connected. You have to connect to your device first and handle things in the connection method.
After you have succeeded in connecting you have to get the service that contains the characteristic you want to use for read, write, notify or indicate.
When you have selected the service You can get the characteristics of that service.
Select the characteristic by Uuid, or in my example with CharacteristicProperties.HasFlag.
This flag in my example is Notify.
In the code comments you find extra info.
using System;
using System.Diagnostics;
using System.Threading.Tasks;
using Windows.Devices.Bluetooth;
using Windows.Devices.Bluetooth.GenericAttributeProfile;
using Windows.Devices.Enumeration;
using Windows.UI.Popups;
using Windows.UI.Xaml.Controls;
namespace App1
{
public sealed partial class MainPage : Page
{
GattDeviceServicesResult serviceResult = null;
private BluetoothLEDevice myDevice;
private GattCharacteristic selectedCharacteristic;
public MainPage()
{
this.InitializeComponent();
ConnectDevice();
}
private async void ConnectDevice()
{
//This works only if your device is already paired!
foreach (DeviceInformation di in await DeviceInformation.FindAllAsync(BluetoothLEDevice.GetDeviceSelector()))
{
BluetoothLEDevice bleDevice = await BluetoothLEDevice.FromIdAsync(di.Id);
// Display BLE device name
var dialogBleDeviceName = new MessageDialog("BLE Device Name " + bleDevice.Name);
await dialogBleDeviceName.ShowAsync();
myDevice = bleDevice;
}
if (myDevice != null)
{
int servicesCount = 3;//Fill in the amount of services from your device!!!!!
int tryCount = 0;
bool connected = false;
while (!connected)//This is to make sure all services are found.
{
tryCount++;
serviceResult = await myDevice.GetGattServicesAsync();
if (serviceResult.Status == GattCommunicationStatus.Success && serviceResult.Services.Count >= servicesCount)
{
connected = true;
Debug.WriteLine("Connected in " + tryCount + " tries");
}
if (tryCount > 5)//make this larger if faild
{
Debug.WriteLine("Failed to connect to device ");
return;
}
}
if (connected)
{
for (int i = 0; i < serviceResult.Services.Count; i++)
{
var service = serviceResult.Services[i];
//This must be the service that contains the Gatt-Characteristic you want to read from or write to !!!!!!!.
string myServiceUuid = "0000ffe0-0000-1000-8000-00805f9b34fb";
if (service.Uuid.ToString() == myServiceUuid)
{
Get_Characteriisics(service);
break;
}
}
}
}
}
private async void Get_Characteriisics(GattDeviceService myService)
{
var CharResult = await myService.GetCharacteristicsAsync();
if (CharResult.Status == GattCommunicationStatus.Success)
{
foreach (GattCharacteristic c in CharResult.Characteristics)
{
if (c.CharacteristicProperties.HasFlag(GattCharacteristicProperties.Notify))
{
selectedCharacteristic = c;
break;
}
}
try
{
// Write the ClientCharacteristicConfigurationDescriptor in order for server to send notifications.
var result = await selectedCharacteristic.WriteClientCharacteristicConfigurationDescriptorAsync(
GattClientCharacteristicConfigurationDescriptorValue.Notify);
if (result == GattCommunicationStatus.Success)
{
var dialogNotifications = new MessageDialog("Successfully registered for notifications");
await dialogNotifications.ShowAsync();
selectedCharacteristic.ValueChanged += SelectedCharacteristic_ValueChanged;
}
else
{
var dialogNotifications = new MessageDialog($"Error registering for notifications: {result}");
await dialogNotifications.ShowAsync();
}
}
catch (Exception ex)
{
// This usually happens when not all characteristics are found
// or selected characteristic has no Notify.
var dialogNotifications = new MessageDialog(ex.Message);
await dialogNotifications.ShowAsync();
await Task.Delay(100);
Get_Characteriisics(myService); //try again
//!!! Add a max try counter to prevent infinite loop!!!!!!!
}
}
else
{
var dialogNotifications = new MessageDialog("Restricted service. Can't read characteristics");
await dialogNotifications.ShowAsync();
}
}
private void SelectedCharacteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
{
}
}
}
If you have problems with this code feel free to ask in comments.

.Net DownloadFileTaskAsync robust WPF code

The WPF code below hangs forever when network connection is lost for 3 or more minutes. When connection is restored it neither throws nor continues downloading nor timeouts. If network connection is lost for a shorter period say half a minute, it throws after connection is restored. How can i make it more robust to survive network outage?
using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Windows;
namespace WebClientAsync
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
NetworkChange.NetworkAvailabilityChanged +=
(sender, e) => Dispatcher.Invoke(delegate()
{
this.Title = "Network is " + (e.IsAvailable ? " available" : "down");
});
}
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
private async void btnDownload_Click(object sender, RoutedEventArgs e)
{
btnDownload.IsEnabled = false;
btnDownload.Content = "Downloading " + SRC;
try {
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
await wcl.DownloadFileTaskAsync(new Uri(SRC), TARGET);
btnDownload.Content = "Downloaded";
}
}
catch (Exception ex)
{
btnDownload.Content = ex.Message + Environment.NewLine
+ ((ex.InnerException != null) ? ex.InnerException.Message : String.Empty);
}
btnDownload.IsEnabled = true;
}
}
}
UPDATE
Current solution is based on restarting Timer in DownloadProgressChangedEventHandler, so the timer fires only if no DownloadProgressChanged events occur within the timeout. Looks like an ugly hack, still looking for a better solution.
using System;
using System.Net;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
namespace WebClientAsync
{
public partial class MainWindow : Window
{
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
// Time needed to restore network connection
const int TIMEOUT = 30 * 1000;
public MainWindow()
{
InitializeComponent();
}
private async void btnDownload_Click(object sender, RoutedEventArgs e)
{
btnDownload.IsEnabled = false;
btnDownload.Content = "Downloading " + SRC;
CancellationTokenSource cts = new CancellationTokenSource();
CancellationToken token = cts.Token;
Timer timer = new Timer((o) =>
{
// Force async cancellation
cts.Cancel();
}
, null //state
, TIMEOUT
, Timeout.Infinite // once
);
DownloadProgressChangedEventHandler handler = (sa, ea) =>
{
// Restart timer
if (ea.BytesReceived < ea.TotalBytesToReceive && timer != null)
{
timer.Change(TIMEOUT, Timeout.Infinite);
}
};
btnDownload.Content = await DownloadFileTA(token, handler);
// Note ProgressCallback will fire once again after awaited.
timer.Dispose();
btnDownload.IsEnabled = true;
}
private async Task<string> DownloadFileTA(CancellationToken token, DownloadProgressChangedEventHandler handler)
{
string res = null;
WebClient wcl = new WebClient();
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
wcl.DownloadProgressChanged += handler;
try
{
using (token.Register(() => wcl.CancelAsync()))
{
await wcl.DownloadFileTaskAsync(new Uri(SRC), TARGET);
}
res = "Downloaded";
}
catch (Exception ex)
{
res = ex.Message + Environment.NewLine
+ ((ex.InnerException != null) ? ex.InnerException.Message : String.Empty);
}
wcl.Dispose();
return res;
}
}
}

You need to implement proper timeout for that download. But you don't need to use timer, just use Task.Delay and Task.WaitAny. For example:
static async Task DownloadFile(string url, string output, TimeSpan timeout) {
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
var download = wcl.DownloadFileTaskAsync(url, output);
// await two tasks - download and delay, whichever completes first
await Task.WhenAny(Task.Delay(timeout), download);
var exception = download.Exception; // need to observe exception, if any
bool cancelled = !download.IsCompleted && exception == null;
// download is not completed yet, nor it is failed - cancel
if (cancelled) {
wcl.CancelAsync();
}
if (cancelled || exception != null) {
// delete partially downloaded file if any (note - need to do with retry, might not work with a first try, because CancelAsync is not immediate)
int fails = 0;
while (true) {
try {
File.Delete(output);
break;
}
catch {
fails++;
if (fails >= 10)
break;
await Task.Delay(1000);
}
}
}
if (exception != null) {
throw new Exception("Failed to download file", exception);
}
if (cancelled) {
throw new Exception($"Failed to download file (timeout reached: {timeout})");
}
}
}
Usage:
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
// Time needed to restore network connection
TimeSpam TIMEOUT = TimeSpan.FromSeconds(30);
DownloadFile(SRC,TARGET, TIMEOUT); // might want to await this to handle exceptions
Update in response to comment. If you want timeout based on received data, not on whole operation time, it's also possible with Task.Delay. For example:
static async Task DownloadFile(string url, string output, TimeSpan timeout)
{
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
DateTime? lastReceived = null;
wcl.DownloadProgressChanged += (o, e) =>
{
lastReceived = DateTime.Now;
};
var download = wcl.DownloadFileTaskAsync(url, output);
// await two tasks - download and delay, whichever completes first
// do that until download fails, completes, or timeout expires
while (lastReceived == null || DateTime.Now - lastReceived < timeout) {
await Task.WhenAny(Task.Delay(1000), download); // you can replace 1 second with more reasonable value
if (download.IsCompleted || download.IsCanceled || download.Exception != null)
break;
}
var exception = download.Exception; // need to observe exception, if any
bool cancelled = !download.IsCompleted && exception == null;
// download is not completed yet, nor it is failed - cancel
if (cancelled)
{
wcl.CancelAsync();
}
if (cancelled || exception != null)
{
// delete partially downloaded file if any (note - need to do with retry, might not work with a first try, because CancelAsync is not immediate)
int fails = 0;
while (true)
{
try
{
File.Delete(output);
break;
}
catch
{
fails++;
if (fails >= 10)
break;
await Task.Delay(1000);
}
}
}
if (exception != null)
{
throw new Exception("Failed to download file", exception);
}
if (cancelled)
{
throw new Exception($"Failed to download file (timeout reached: {timeout})");
}
}
}

Personally, if I were to make a robust download solution, I would add a Network connection monitor because that's what we are actually waiting for. For simplicity, something like this will be enough.
online = true;
NetworkChange.NetworkAvailabilityChanged += NetworkChange_NetworkAvailabilityChanged;
_isNetworkOnline = NetworkInterface.GetIsNetworkAvailable();
void NetworkChange_NetworkAvailabilityChanged(object sender, NetworkAvailabilityEventArgs e)
{
online = e.IsAvailable;
}
Then you can actually check for network availability and wait as appropriate before you attempt to download or progress... I will definitely accept that a simple ping solution seems to work better than this at times based on experience.
Depending on the size of what you're downloading, monitoring the network speed may also help so you can decide how to chunk in case of choppy connections. Take a look at this project for ideas.

My C# multi-threaded console application seems to not be multithreaded

Here's my C# console program that uses Powerpoint to convert ppt files to folders of pngs. This is supposed to be an automated process that runs on its own server.
I expect that as soon as a thread creates an image from a file, it should immediately remove the images and the source file.
The actual behavior is that, if five threads are running, it'll wait for five folders of images to be created before any thread can move any files. I'm able to see the images being created, and compare that with the Console readout, so I can see that a thread isn't trying to move the file.
Only after all the other threads have made their images, will any thread try to move the files. I suspect this is wrong.
This is an Amazon EC2 Medium instance, and it appears to max out the CPU, so five threads might be too much for this.
I also find that I can hardly use Windows Explorer while this program is running.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.IO;
using Microsoft.Office.Core;
using PowerPoint = Microsoft.Office.Interop.PowerPoint;
using System.Diagnostics;
using System.Timers;
namespace converter
{
class Program
{
public static int threadLimit=0;
public static int currThreads = 0;
static void Main(string[] args)
{
var inDir = args[0];
var outDir = args[1]+"\\";
var procDir = args[2]+"\\";
Int32.TryParse(args[3],out threadLimit);
Thread[] converterThreads = new Thread[threadLimit];
while (true)
{
System.Threading.Thread.Sleep(1000);
var filePaths = Directory.GetFiles(inDir, "*.*", SearchOption.AllDirectories).Where(s => s.EndsWith(".pptx") && !s.Contains("~$") || s.EndsWith(".ppt") && !s.Contains("~$"));
var arrPaths = filePaths.ToArray();
for(var i=0; i< arrPaths.Length; i++)
{
if (currThreads < threadLimit && currThreads < arrPaths.Length)
{
Console.WriteLine("currThreads= " + currThreads + " paths found= " + arrPaths.Length);
try
{
var fileNameWithoutExtension = arrPaths[currThreads].Replace(inDir, "").Replace(".pptx", "").Replace(".ppt", "").Replace("\\", "");
var filenameWithExtension = arrPaths[currThreads].Substring(arrPaths[currThreads].LastIndexOf("\\") + 1);
var dir = arrPaths[currThreads].Replace(".pptx", "").Replace(".ppt", "");
Conversion con = new Conversion(arrPaths[currThreads], dir, outDir, procDir, filenameWithExtension, fileNameWithoutExtension);
converterThreads[i] = new Thread(new ThreadStart(con.convertPpt));
converterThreads[i].Start();
Console.WriteLine(converterThreads[i].ManagedThreadId + " is converting " + fileNameWithoutExtension);
}
catch (Exception e)
{
Console.WriteLine(string.Format("Unable to convert {0} ", arrPaths[i]) + e);
}
}
}
for (var i = 0; i < converterThreads.Length; i++)
{
if (converterThreads[i] != null)
{
if (!converterThreads[i].IsAlive)
{
converterThreads[i].Abort();
converterThreads[i].Join(1);
Console.WriteLine("thread " + converterThreads[i].ManagedThreadId + " finished, "+currThreads+" remaining");
converterThreads[i] = null;
}
}
}
if (currThreads == 0)
{
try
{
foreach (Process proc in Process.GetProcessesByName("POWERPNT"))
{
proc.Kill();
}
}
catch (Exception e3)
{
}
}
}
}
}
class Logger{
static void toLog(String msg)
{
//TODO: log file
}
}
class Conversion{
static int numberOfThreads=0;
String input;
String output;
String outDir;
String process;
String nameWith;
String nameWithout;
int elapsedTime;
System.Timers.Timer time;
public Conversion(String input, String output, String outDir, String processDir, String nameWith, String nameWithout)
{
this.input = input;
this.output = output;
this.outDir = outDir;
process = processDir;
this.nameWith = nameWith;
this.nameWithout = nameWithout;
numberOfThreads++;
Console.WriteLine("number of threads running: " + numberOfThreads);
Program.currThreads = numberOfThreads;
time = new System.Timers.Timer(1000);
time.Start();
time.Elapsed += new ElapsedEventHandler(OnTimedEvent);
elapsedTime = 0;
}
private void OnTimedEvent(object source, ElapsedEventArgs e)
{
elapsedTime++;
}
public void convertPpt()
{
var app = new PowerPoint.Application();
var pres = app.Presentations;
try
{
var file = pres.Open(input, MsoTriState.msoFalse, MsoTriState.msoFalse, MsoTriState.msoFalse);
file.SaveAs(output, Microsoft.Office.Interop.PowerPoint.PpSaveAsFileType.ppSaveAsPNG, MsoTriState.msoTrue);
file.Close();
app.Quit();
Console.WriteLine("file converted " + input);
}
catch (Exception e)
{
Console.WriteLine("convertPpt failed");
}
moveFile();
moveDir();
}
public void moveFile()
{
Console.WriteLine("moving" + input);
try
{
System.Threading.Thread.Sleep(500);
Console.WriteLine(string.Format("moving {0} to {1}", input, process + nameWith));
if (File.Exists(process + nameWith))
{
File.Replace(input, process + nameWith, null);
}
else
{
File.Move(input, process + nameWith);
}
}
catch (Exception e)
{
Console.WriteLine(string.Format("Unable to move the file {0} ", input) + e);
try
{
foreach (Process proc in Process.GetProcessesByName("POWERPNT"))
{
proc.Kill();
}
}
catch (Exception e3)
{
}
}
}
public void moveDir()
{
Console.WriteLine("moving dir " + output);
try
{
System.Threading.Thread.Sleep(500);
Console.WriteLine(string.Format("moving dir {0} to {1} ", output, outDir + nameWithout));
if (Directory.Exists(outDir + nameWithout))
{
Directory.Delete(outDir + nameWithout, true);
}
if (Directory.Exists(output))
{
Directory.Move(output, outDir + nameWithout);
}
}
catch (Exception e)
{
Console.WriteLine(string.Format("Unable to move the directory {0} ", output) + e);
try
{
foreach (Process proc in Process.GetProcessesByName("POWERPNT"))
{
proc.Kill();
}
}
catch (Exception e3)
{
}
}
finally
{
numberOfThreads--;
Program.currThreads = numberOfThreads;
Console.WriteLine("took " + elapsedTime + "seconds");
}
}
}
}

Every 1000ms you get a list of files in inDir and potentially start a thread to process each file. You have very complex logic surrounding whether or not to start a new thread, and how to manage the lifetime of the thread.
The logic is too complex for me to spot the error without debugging the code. However, I would propose an alternative.
Have a single thread watch for new files and place the file path into a BlockingCollection of files for processing. That thread does nothing else.
Have N additional threads that retrieve file paths from the BlockingCollection and process them.
This is known as a Producer / Consumer pattern and is ideal for what you are doing.
The example code at the bottom of the linked MSDN page shows an implementation example.
On a side note, you are catching and swallowing Exception e3. Don't catch something you will not handle, it hides problems.

SMS connecting to a phone from C# and getting a response

I wrote code to send an SMS using my GSM phone which is attached to the computer through COM port. The code is below.
The problem is I do see that it is in the outbox of the phone and it actually appears to have been sent, but when I contact the recipient they say that I have not received the message.
I test the phone, and I create and send a message using only the phone and it works perfectly. However, when I do this with my code, it APPEARS to have been sent, and I am getting all the correct AT COMMAND responses from the phone, but the message is actually NOT sent.
Here is the code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Threading;
using System.IO.Ports;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
SerialPort serialPort1;
int m_iTxtMsgState = 0;
const int NUM_MESSAGE_STATES = 4;
const string RESERVED_COM_1 = "COM1";
const string RESERVED_COM_4 = "COM4";
public Form1()
{
InitializeComponent();
this.Closing += new CancelEventHandler(Form1_Closing);
}
private void Form1_Load(object sender, EventArgs e)
{
serialPort1 = new SerialPort(GetUSBComPort());
if (serialPort1.IsOpen)
{
serialPort1.Close();
}
serialPort1.Open();
//ThreadStart myThreadDelegate = new ThreadStart(ReceiveAndOutput);
//Thread myThread = new Thread(myThreadDelegate);
//myThread.Start();
this.serialPort1.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived);
}
private void Form1_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
serialPort1.Close();
}
private void SendLine(string sLine)
{
serialPort1.Write(sLine);
sLine = sLine.Replace("\u001A", "");
consoleOut.Text += sLine;
}
public void DoWork()
{
ProcessMessageState();
}
public void ProcessMessageState()
{
switch (m_iTxtMsgState)
{
case 0:
m_iTxtMsgState = 1;
SendLine("AT\r\n"); //NOTE: SendLine must be the last thing called in all of these!
break;
case 1:
m_iTxtMsgState = 2;
SendLine("AT+CMGF=1\r\n");
break;
case 2:
m_iTxtMsgState = 3;
SendLine("AT+CMGW=" + Convert.ToChar(34) + "+9737387467" + Convert.ToChar(34) + "\r\n");
break;
case 3:
m_iTxtMsgState = 4;
SendLine("A simple demo of SMS text messaging." + Convert.ToChar(26));
break;
case 4:
m_iTxtMsgState = 5;
break;
case 5:
m_iTxtMsgState = NUM_MESSAGE_STATES;
break;
}
}
private string GetStoredSMSID()
{
return null;
}
/* //I don't think this part does anything
private void serialPort1_DataReceived_1(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
string response = serialPort1.ReadLine();
this.BeginInvoke(new MethodInvoker(() => textBox1.AppendText(response + "\r\n")));
}
*/
void sp_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
try
{
Thread.Sleep(500);
char[] msg;
msg = new char[613];
int iNumToRead = serialPort1.BytesToRead;
serialPort1.Read(msg, 0, iNumToRead);
string response = new string(msg);
this.BeginInvoke(new MethodInvoker(() => textBox1.AppendText(response + "\r\n")));
serialPort1.DiscardInBuffer();
if (m_iTxtMsgState == 4)
{
int pos_cmgw = response.IndexOf("+CMGW:");
string cmgw_num = response.Substring(pos_cmgw + 7, 4);
SendLine("AT+CMSS=" + cmgw_num + "\r\n");
//stop listening to messages received
}
if (m_iTxtMsgState < NUM_MESSAGE_STATES)
{
ProcessMessageState();
}
}
catch
{ }
}
private void button1_Click(object sender, EventArgs e)
{
m_iTxtMsgState = 0;
DoWork();
}
private void button2_Click(object sender, EventArgs e)
{
string[] sPorts = SerialPort.GetPortNames();
foreach (string port in sPorts)
{
consoleOut.Text += port + "\r\n";
}
}
private string GetUSBComPort()
{
string[] sPorts = SerialPort.GetPortNames();
foreach (string port in sPorts)
{
if (port != RESERVED_COM_1
&& port != RESERVED_COM_4)
{
return port;
}
}
return null;
}
}

This is my code that works (tested) with U9 Telia cellular modem:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Configuration;
using UsbEject.Library;
using Utils;
namespace Hardware
{
public class TeliaModem : IDisposable
{
public delegate void NewSmsHandler(InboundSMS sms);
public event NewSmsHandler OnNewSMS;
#region private data
System.IO.Ports.SerialPort modemPort;
Timeouter _lastModemKeepAlive;
private delegate void DataReceivedDelegate();
private DataReceivedDelegate dataReceivedDelegate;
Queue<OutboundSMS> _outSmses = new Queue<OutboundSMS>();
enum ModemState
{
Error = -1, NotInitialized, PowerUp, Initializing, Idle,
SendingSMS, KeepAliveAwaitingResponse
};
Timeouter ModemStateTimeouter = new Timeouter(timeout_s: 10, autoReset: false);
ModemState _modemState = ModemState.NotInitialized;
ModemState CurrentModemState
{
get
{
return _modemState;
}
set
{
_modemState = value;
ModemStateTimeouter.Reset();
NihLog.Write(NihLog.Level.Debug, "State changed to: " + value.ToString());
}
}
private System.Windows.Forms.Control _mainThreadOwnder;
#endregion
public TeliaModem(System.Windows.Forms.Control mainThreadOwnder)
{
_mainThreadOwnder = mainThreadOwnder;
dataReceivedDelegate = new DataReceivedDelegate(OnDataReceived);
}
public void SendSMS(string phone, string text)
{
_outSmses.Enqueue(new OutboundSMS(phone, text));
HeartBeat();
}
private void SendSmsNow()
{
OutboundSMS sms = _outSmses.Peek();
sms.Attempt++;
if (sms.Attempt > sms.MaxTries)
{
NihLog.Write(NihLog.Level.Error, "Failure to send after " + sms.MaxTries + " tries");
_outSmses.Dequeue();
return;
}
NihLog.Write(NihLog.Level.Info, "Sending SMS: " + sms.ToString());
WriteToModem("AT+CMGS=\"" + sms.Destination + "\"\r");
System.Threading.Thread.Sleep(500);
WriteToModem(sms.Text);
byte[] buffer = new byte[1];
buffer[0] = 26; // ^Z
modemPort.Write(buffer, offset:0, count:1);
CurrentModemState = ModemState.SendingSMS;
}
public void Dispose()
{
UninitModem();
}
public void HeartBeat()
{
if (CurrentModemState == ModemState.NotInitialized)
{
TryInitModem();
return;
}
if (IsTransitionalState(CurrentModemState) && ModemStateTimeouter.IsTimedOut())
{
NihLog.Write(NihLog.Level.Error, "Modem error. Timed out during " + CurrentModemState);
CurrentModemState = ModemState.Error;
return;
}
if (CurrentModemState == ModemState.Idle && _lastModemKeepAlive.IsTimedOut())
{
// Send keepalive
WriteToModem("AT\r");
CurrentModemState = ModemState.KeepAliveAwaitingResponse;
return;
}
if (CurrentModemState == ModemState.Error)
{
NihLog.Write(NihLog.Level.Debug, "Reenumerating modem...");
UninitModem();
return;
}
if (_outSmses.Count != 0 && CurrentModemState == ModemState.Idle)
{
SendSmsNow();
return;
}
}
private string pendingData;
private void OnDataReceived()
{
// Called in the main thread
string nowWhat = modemPort.ReadExisting();
pendingData += nowWhat;
string[] lines = pendingData.Split(new string[] { "\r\n" }, StringSplitOptions.None);
if (lines.Length == 0)
{
pendingData = string.Empty;
return;
}
else
{
pendingData = lines[lines.Length - 1];
}
// This happens in main thread.
for (int i = 0; i < lines.Length - 1; i++)
{
string line = lines[i];
if (line.Length >= 5 && line.Substring(0, 5) == "+CMT:")
{
// s+= read one more line
if (i == lines.Length - 1) // no next line
{
pendingData = line + "\r\n" + pendingData; // unread the line
continue;
}
string line2 = lines[++i];
NihLog.Write(NihLog.Level.Debug, "RX " + line);
NihLog.Write(NihLog.Level.Debug, "RX " + line2);
InboundSMS sms = new InboundSMS();
sms.ParseCMT(line, line2);
if(OnNewSMS != null)
OnNewSMS(sms);
}
else // Not a composite
NihLog.Write(NihLog.Level.Debug, "RX " + line);
if (line == "OK")
{
OnModemResponse(true);
}
else if (line == "ERROR")
{
OnModemResponse(false);
NihLog.Write(NihLog.Level.Error, "Modem error");
}
}
}
private void ProcessSmsResult(bool ok)
{
if (!ok)
{
OutboundSMS sms = _outSmses.Peek();
if (sms.Attempt < sms.MaxTries)
{
NihLog.Write(NihLog.Level.Info, "Retrying sms...");
return;
}
NihLog.Write(NihLog.Level.Error, "Failed to send SMS: " + sms.ToString());
}
_outSmses.Dequeue();
}
private void OnModemResponse(bool ok)
{
if (CurrentModemState == ModemState.SendingSMS)
ProcessSmsResult(ok);
if (!ok)
{
NihLog.Write(NihLog.Level.Error, "Error during state " + CurrentModemState.ToString());
CurrentModemState = ModemState.Error;
return;
}
switch (CurrentModemState)
{
case ModemState.NotInitialized:
return;
case ModemState.PowerUp:
WriteToModem("ATE0;+CMGF=1;+CSCS=\"IRA\";+CNMI=1,2\r");
CurrentModemState = ModemState.Initializing;
break;
case ModemState.Initializing:
case ModemState.SendingSMS:
case ModemState.KeepAliveAwaitingResponse:
CurrentModemState = ModemState.Idle;
break;
}
}
private void CloseU9TelitNativeApp()
{
bool doneSomething;
do
{
doneSomething = false;
Process[] processes = Process.GetProcessesByName("wirelesscard");
foreach (Process p in processes)
{
p.CloseMainWindow();
doneSomething = true;
NihLog.Write(NihLog.Level.Info, "Killed native U9 app");
System.Threading.Thread.Sleep(1000); // Will not wait if no native app is started
}
} while (doneSomething);
}
void WriteToModem(string s)
{
modemPort.Write(s);
NihLog.Write(NihLog.Level.Debug, "TX " + s);
}
void UninitModem()
{
if (modemPort != null)
modemPort.Dispose();
modemPort = null;
CurrentModemState = ModemState.NotInitialized;
}
private bool IsTransitionalState(ModemState ms)
{
return ms == ModemState.Initializing
|| ms == ModemState.SendingSMS
|| ms == ModemState.PowerUp
|| ms == ModemState.KeepAliveAwaitingResponse;
}
Timeouter _initFailureTimeout =
new Timeouter(timeout_s: 10, autoReset:false, timedOut:true);
void TryInitModem()
{
// Try pistoning the modem with higher frequency. This does no harm (such as redundant logging)
PrepareU9Modem(); // Will do nothing if modem is okay
if (!_initFailureTimeout.IsTimedOut())
return; // Don't try too frequently
if (modemPort != null)
return;
const string modemPortName = "Basecom HS-USB NMEA 9000";
const int speed = 115200;
string portName = Hardware.Misc.SerialPortFromFriendlyName(modemPortName);
if (portName == null)
{
NihLog.Write(NihLog.Level.Error, "Modem not found (yet). ");
_initFailureTimeout.Reset();
return;
}
NihLog.Write(NihLog.Level.Info, string.Format("Found modem port \"{0}\" at {1}", modemPortName, portName));
modemPort = new System.IO.Ports.SerialPort(portName, speed);
modemPort.ReadTimeout = 3000;
modemPort.NewLine = "\r\n";
modemPort.Open();
modemPort.DiscardInBuffer();
modemPort.DataReceived += new System.IO.Ports.SerialDataReceivedEventHandler(delegate { _mainThreadOwnder.Invoke(dataReceivedDelegate); }); // called in different thread!
_lastModemKeepAlive = new Timeouter(60, true);
WriteToModem("AT+CFUN=1\r");
CurrentModemState = ModemState.PowerUp;
}
void CheatU9Telit()
{
// U9 telit appears as USB CDrom on the bus, until disk eject is sent.
// Then, it reappears as normal stuff.
VolumeDeviceClass volumeDeviceClass = new VolumeDeviceClass();
foreach (Volume device in volumeDeviceClass.Devices)
{
if (device.FriendlyName == "PCL HSUPA Modem USB Device")
{
NihLog.Write(NihLog.Level.Info, "Trying to initialize: " + device.FriendlyName);
device.EjectCDRomNoUI();
}
}
}
void PrepareU9Modem()
{
CloseU9TelitNativeApp(); // Closes the autorun native app
CheatU9Telit();
}
}
public class OutboundSMS
{
public string Destination;
public string Text;
public int MaxTries;
public int Attempt = 0;
public OutboundSMS(string dest, string txt)
{
Destination = dest;
Text = txt;
MaxTries = 3;
}
override public string ToString()
{
if(Attempt > 1)
return string.Format("\"{0}\" to {1}, attempt {2}",
Text, Destination, Attempt);
else
return string.Format("\"{0}\" to {1}",
Text, Destination);
}
}
public class InboundSMS
{
public string SourcePhone;
public DateTime ReceiveTime;
public string Text;
public void ParseCMT(string line1, string line2)
{
string[] fields = line1.Split(new char[] { ',', ' ', '/', ':', '"' });
if (fields.Length < 12)
throw new ApplicationException("CMT message too short. Expected 2 fields");
SourcePhone = fields[3];
ReceiveTime = DateTime.Parse("20" + fields[7] + "-" + fields[8] + "-" + fields[9] + " " + fields[10] + ":" + fields[11] + ":" + fields[12].Substring(0, 2)); //test carefully
Text = line2;
}
};
}
Usage example in a winforms application:
Hardware.TeliaModem _modem;
public Form1()
{
InitializeComponent();
_modem = new Hardware.TeliaModem(this);
_modem.OnNewSMS += new Hardware.TeliaModem.NewSmsHandler(ProcessNewSMS);
_timer.Interval = 1000; // milliseconds
_timer.Tick += new EventHandler(OnTimerTick);
_timer.Start();
}
To send an SMS:
_modem.SendSMS(sms.SourcePhone, "Aircon is now " + BoolToString.ON_OFF(_aircon.On));
On timer event, once every second:
private void OnTimerTick(object o, EventArgs e)
{
_modem.HeartBeat();
}
This is registered as Winforms timer handler, so that modem will not have a thread.
Some utility classes used:
namespace Utils
{
public class StopWatch
{
protected DateTime _resetTime;
public StopWatch() { Reset(); }
public void Reset() { _resetTime = DateTime.Now; }
public double TotalSeconds { get { return (DateTime.Now - _resetTime).TotalSeconds; } }
public TimeSpan Time { get { return DateTime.Now - _resetTime; } }
};
public class Timeouter : StopWatch
{
private bool _autoReset;
private double _timeout_s;
public Timeouter(double timeout_s, bool autoReset, bool timedOut = false)
{
_timeout_s = timeout_s;
_autoReset = autoReset;
if (timedOut)
_resetTime -= TimeSpan.FromSeconds(_timeout_s + 1); // This is surely timed out, as requested
}
public bool IsTimedOut()
{
if (_timeout_s == double.PositiveInfinity)
return false;
bool timedout = this.TotalSeconds >= _timeout_s;
if (timedout && _autoReset)
Reset();
return timedout;
}
public void Reset(double timeout_s) { _timeout_s = timeout_s; Reset(); }
public double TimeLeft { get { return _timeout_s - TotalSeconds; } }
}
}
I implemented this in order to turn on air conditioner with SMS (yeah, I live in a hot country). It works. Please feel free to use any of this code.
Enjoy.

Microsoft provides a pretty decent VB.Net example in a KB article "How to access serial and parallel ports by using Visual Basic .NET". I'm not sure what your phone returns, however, if you change the buffer loop in the example, you can at least print out the reply:
MSComm1.Output = "AT" & Chr(13)
Console.WriteLine("Send the attention command to the modem.")
Console.WriteLine("Wait for the data to come back to the serial port...")
' Make sure that the modem responds with "OK".
' Wait for the data to come back to the serial port.
Do
Buffer = Buffer & MSComm1.Input
Console.WriteLine("Found: {0}", Buffer)
Loop Until InStr(Buffer, "OK" & vbCrLf)

GSMComm is a C# library that will allow you to easily interact with a GSM mobile in text or PDU mode. (The site also has a bunch of testing utilities)

Working with GSM modem to send SMS has never been a good idea as such. Here's a checklist to make sure your SMS is sent out properly.
You are sending the SMS in text mode. Try sending it in PDU mode.
Try this library http://phonemanager.codeplex.com/
Do you change SMSC number before sending out the SMS, if so make sure the SMSC is correct.
Also make sure your SIM card has enough credits to let you send outbound SMS.
Check the network status especially when you're sending out SMS from your program. This might be a problem.
I recommend you checkout the Lite edition of NowSMS gateway that comes for free and lets you work with GSM modem very continently. NowSMS will give you api abstraction over a GSM modem connection, so you wil just need to call the Http Api of NowSMS gateway, rest will be taken care by the NowSMS gateway.
Above all this, if your end-users are going to remain internet connected while using your application or if your application is web-based and hosted over internet, I strongly recoomend to do away with GSM modem option and opt-in for reliable Http SMS gateway service providers.