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Strange behaviour when communicating over serial from VS WPF to Arduino

A basic overview. I am sending serial data from an Arduino Due to WPF application. Up until now this has all been working perfectly. Today I implemented a loop into the Arduino code that looks for a "Y" (ascii 89) in the serial port, if received it leaves the loop and returns back into what I am calling offline mode and stops sending over data, via online = false.
Now what is strange about this is that...
It was working fine before this loop so it must be something to do with trying to resend new data once it has left the 'online loop'.
It works perfectly from the Arduino serial monitor, which suggests it's a WPF problem, although the code hasn't changed on the upload section.
The code for both of these programmes is pretty big so I will try and keep it concise whilst providing all the information necessary.
void loop() {
// Check to see if the testbench is in offline mode and run the respective code.
if (Online == false) {
OfflineMode();
}
// Check to see if the testbench is in online mode and run the respective code.
if (Online == true) {
OnlineMode();
}
}
void OfflineMode() {
while (Serial.available())
processlncomingByte(Serial.read());
}
I then have switch cases to handle incoming settings - I know this works fine as it will also upload after the Arduino is reset.
void processlncomingByte (const byte c) {
if (isdigit (c)) {
currentValue *= 10;
currentValue += c - '0';
} else {
// end of digit
// The end of the number signals a state change
handlePreviousState ();
// set the new state, if we recognize it
switch (c) {
case 'A':
state = GOT_A;
break;
etc...
Online Mode
void OnlineMode() {
CheckForStop();
SendSerialData();
}
void CheckForStop() {
//Serial.println("...");
if (Serial.available() > 0) {
//Serial.println("getting something");
ch = (char)Serial.read();
inputString = ch;
if (ch == 89) {
//Serial.end();
Online = false;
//Serial.begin(9600);
exit;
//return;
}
} else
delay(5);
}
SendSerialData() consists of just a range of serial.print, outputting into one large string for WPF to handle.
Here is a screenshot of the serial monitor working
As you will see from the link above the monitor spits out a load of data, stops when I send a Y and finally I send a Q to 'question' whether the Arduino is ready to receive settings and S signifies a Yes. Great stuff it works!
However as you can see from the link below this isn't the case in WPF. Sorry, I can only upload 2 images at the moment so had to combine them.
Combo of screenshots
Here is the loop it is currently getting stuck in
private bool checkArduinoisReady() {
Stopwatch Uploadtimer = new Stopwatch();
if (!myPort.IsOpen)
return false;
// Debug.Print("port is ready to be opened");
string tempdata;
Uploadtimer.Start();
myPort.DiscardInBuffer();
Start:
myPort.WriteLine("Q" + Environment.NewLine);
Debug.Print("sent Q");
tempdata = myPort.ReadExisting();
Debug.Print("tempdata_" + tempdata.ToString());
if (Uploadtimer.ElapsedMilliseconds > 5000)
return false;
if (tempdata.Contains("S"))
return true;
else
goto Start;
}
And on a separate page this is how I am stopping the incoming data.
private void StopTest(object sender, RoutedEventArgs e) {
MessageBoxResult StopConfirm = MessageBox.Show("Are you sure you want to stop the test?", "Stop the test", MessageBoxButton.YesNo, MessageBoxImage.Question);
if (StopConfirm == MessageBoxResult.Yes) {
Timer.Stop();
Debug.Print("Timer Stopped");
myPort.DiscardInBuffer();
Start:
for (int i = 0; i < 100; i++) {
myPort.WriteLine("Y");
}
string tempData = myPort.ReadExisting();
Debug.Print("Checking...");
Debug.Print("tempData_" + tempData);
if (string.IsNullOrWhiteSpace(tempData)) {
Debug.Print("Its null!!");
comments_textbox.Text = comments_textbox.Text + "Test Aborted";
MessageBoxResult SaveCurrentData = MessageBox.Show("Would you like to save the data collected up until this point?", "Save", MessageBoxButton.YesNo, MessageBoxImage.Question);
if (SaveCurrentData == MessageBoxResult.Yes) {
SaveFile();
}
if (SaveCurrentData == MessageBoxResult.No) {
myPort.Close();
NavigationService.Navigate(new Uri("testSettings.xaml", UriKind.RelativeOrAbsolute));
}
} else {
Debug.Print("Still going...");
goto Start;
}
}
}
The biggest stumbling block for me is why this works over the serial monitor but not within the application. And it also works as soon as I reset the Arduino. I have also tried the resetFunc() in Arduino but this didn't help either.
Thanks in advance.

It turns out i still had a resetFunc() in my switch case which was preventing the serial monitor from continuing to send data!

Suppressing global windows shortcuts while recording keypresses

Is it possible to suppress the windows global shortcuts while recording keypresses ?
I have a Windows Form application written in c#, and using this library to record keypresses to use later in macros. Now when I record the key combinations that are used by Windows (i.e. L Control + Win + Right Arrow to change virtual desktop on Win 10), I'd like my app to record it but avoid windows actually using it while I record which is quite annoying.
I have a checkbox to enable key capturing, on click event
m_KeyboardHookManager.KeyDown += HookManager_KeyDown;
the HookManager_KeyDown is simply like this
private void HookManager_KeyDown(object sender, KeyEventArgs e)
{
Log(string.Format("KeyDown \t\t {0}\n", e.KeyCode));
string [] sArr = new string [2];
if (keyBindingArea1.Text != "")
{
sArr[0] = keyBindingArea1.Text;
sArr[1] = string.Format("{0}", e.KeyCode);
keyBindingArea1.Text = string.Join("+", sArr);
}
else
{
keyBindingArea1.Text = string.Format("{0}", e.KeyCode);
}
}
which display the key combination in a comboText control. (This code is taken directly from the demo attached to the package.
Now the recording work well if for instance I press L Control + Win, then I release the keys and press the third one (i.e. Right Arrow), this will not trigger Windows shortcuts but it is quite annoying to have it work like that.
Appreciate any help. Thanks

Try to use e.Handled property of the event. If you set it to true it will terminate key procesing chain. As a rule oher applications in the processing chain will not get it. I am not sure it is going to work for such a low level windows staff as virtual desktop switch.
private void OnKeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
bool isThirdKey = //Some state evaluation to detect the third key was pressed
if (isThirdKey) e.Handled = true;
}

Share text using NFC in Windows Phone 8

I am trying to create an app for learning purpose in which one windows phone 8 user sends the text and other user receives it. And the text is shared through NFC. But the problem is the other user is not able to receive the text.
Here is the code=>
Receiver's Code:
ProximityDevice device;
long subscribedMessageId;
private void receive_Click(object sender, RoutedEventArgs e)
{
device = ProximityDevice.GetDefault();
if (device != null)
{
subscribedMessageId = device.SubscribeForMessage("Windows.SampleMessage", messageReceivedHandler);
}
}
private void messageReceivedHandler(ProximityDevice sender, ProximityMessage message)
{
rtextbox.Text = message.DataAsString;
device.StopSubscribingForMessage(subscribedMessageId);
}
Sender's Code:
ProximityDevice device;
long publishedMessageId;
private void send_Click(object sender, RoutedEventArgs e)
{
device = ProximityDevice.GetDefault();
device.StopPublishingMessage(publishedMessageId);
if (device != null)
{
publishedMessageId = device.PublishMessage("Windows.SampleMessage", textbox1.Text);
textbox1.Text = "";
}
}
Both the codes are present on different page. Code is executed when the user clicks on send or receive button respectively.
I am new to NFC so any help will be appreciated.

Unfortunately, NFC gets complicated. There's quite a bit of plumbing involved to handle peer-to-peer communication seamlessly. It's far too much to put into an answer here on the site, so I will have to resort to links.
You can check out this Nokia article and project to work through your understanding of the plumbing and get an application going that will exchange text. http://developer.nokia.com/Resources/Library/Lumia/#!code-examples/nfc-talk.html
Then, if you want to take it up a notch, you can work through this article to upgrade your app to allow image transfer functionality as well. http://developer.nokia.com/Community/Wiki/Transfer_an_Image_with_NFC

Serial Communication in C# using arduino, android, winform

I have a program that is similar to an ATM application. I use my android device a the Keypad. No problem with transmitting data from phone to my C# program. I use threading. I have a problem on how to really "start" the ATM application.
The only input device is the android device. I will not use computer keyboard or anything. So once the program is shown, the first thing is that the program will ask what kind of transaction is it.
private void FrontPage_Shown(object sender, EventArgs e)
{
Ask_Transaction();
}
and inside that... (Edited part)
public void Ask_Transaction()
{
string decoded_input = "";
decoded_input = KT.CheckPress(input); //"input" is the data from the arduino. the checkpress will decode it.
do
{
try
{
//input = serialPort.ReadLine();
switch (KT.CheckPress(input))
{
case "S5": //Card;
break;
case "S6": //Cardless
{
PF.Format_Cardless();
AskLanguage(); //if cardless, it will now ask the language. Once again, another input from serial is needed
}
break;
case "Cancel": PF.Format_TransactionCancelled();
break;
default:
break;
}
}
catch
{
//To catch ReadTimeout after 6 seconds
//"You do not respond to the alloted time.."
}
}
while (decoded_input != "S5"
|| decoded_input != "S6"
|| decoded_input != "Cancel");
}
my problem is that when I try to loop Ask_Transaction until I get the correct inputs (S5 or S6 or cancel) using a do-while loop, my program is lagging and eventually crashing. No errors displaying.
EDIT:
Of course we cannot assure that the user will input the correct key. And usually when you click just numbers on the keypad, ATM program will not notify you at first. It will just wait for possible correct inputs. Also, if the user enters S6, the program will now ask another input using those keypad numbers s5 and s6. the problem is that the program is not "continuous". Any kind of help will be appreciated.

DeviceLostException during CTRL ALT DEL in Direct3D using C#

I am using the Microsoft.DirectX and Microsoft.DirectX.Direct3D references to do some drawing on my form. While I am running the program and the user presses CTRL ALT DEL in Windows XP and brings up the "Windows Security" form, when returning back to the Form, a DeviceLostException is thrown and when trying to handle this exception there seems to be no way to get it back.
I have done a little research into the matter and have tried several coding solutions.
try
{
_d3ddevice.Present();
}
catch
{
DeviceLost = true;
}
if (DeviceLost)
{
AttemptRecovery();
}
this.Invalidate();
ReadKeyboard();
base.OnPaint(e);
}
private void AttemptRecovery()
{
try
{
_d3ddevice.TestCooperativeLevel();
}
catch (DeviceLostException)
{
Application.Exit();
}
catch (DeviceNotResetException)
{
try
{
_d3ddevice.Reset(_params);
DeviceLost = false;
InitGraphics();
CameraPositioning();
VertexDeclaration();
IndicesDeclaration();
}
catch (DeviceLostException)
{
}
}
}
When the program calls TestCooperativeLevel(), it said online if it catches the DeviceLostException again that there is no point in trying to reset the device.
What can I do to reset the device and continue drawing in my form?

2 things in 4 points :
You shouldn't use Microsoft.DirectX, it's deprecated since a long, long time. Check out SlimDX or SharpDX instead.
In order to re-create your device, you first have to wait until the device can be restored
When the device can be restored, you have to free all video-memory objects, and recreate them.
You call the Reset method.