when using while loop in the progam, the application is not exiting - visual-c++

Question

I have created an application in visual studio 2012 c++. The idea is to read the data from the serial port and to change the color for the label accordingly.I have used while loop to change the color in a continuous manner. Now, the application is working perfectly. The problem am facing is the application not existing when i click on the exit button or 'x' button in the application.I can able to close only in task manager by clicking on end task. The following is code of my application. Please let me know is there any way to fix this problem
while(checkBox1->Checked)
{
if(this->serialPort1->IsOpen)
{
int b[4] = {0};
int *ptr1;
ptr1 = b;
//this->serialPort1->DiscardInBuffer();
for (int i=0; i<4; i++)
{
*ptr1 = this->serialPort1->ReadChar();
ptr1++;
}
int address;
address = ((b[0]-48)*10)+(b[1]-48);
System::Windows::Forms::Label ^ ptr;
switch (address)
{
case 1: ptr = label1;
break;
case 2: ptr = label2;
break;
case 3: ptr = label3;
break;
case 4: ptr = label4;
break;
case 5: ptr = label5;
break;
case 6: ptr = label6;
break;
case 7: ptr = label7;
break;
case 8: ptr = label8;
break;
default: //MessageBox::Show("Default Case");
break;
}
if(b[2]=='o')
{
ptr->BackColor = Color::Red;
ptr->Text="R";
}
else if(b[2]=='a')
{
ptr->Text=String::Empty;
ptr->BackColor = Color::Green;
}
else if(b[2]=='i')
{
ptr->Text=String::Empty;
ptr->BackColor = Color::Blue;
}
if ((b[3]-48)<3)
{
ptr->Text=String::Empty;
ptr->BackColor = Color::SaddleBrown;
//_sleep(5000);
}

Answer 1

If you do UI programming, you must use an event driven mechanism! In your case, you should register to the "DataReceived" event in order to get called if new data arrives from the port.
private: System::Void serialPort1_DataReceived(System::Object^ sender, System::IO::Ports::SerialDataReceivedEventArgs^ e)
{
array<unsigned char> ^data = gcnew array<unsigned char>(4);
serialPort1->Read(data, 0, 4);
// Do whatever you want...
}
In the event handler "checkBox1_CheckedChanged" you should just open or close the serial port!
private: System::Void checkBox1_CheckedChanged(System::Object^ sender, System::EventArgs^ e)
{
if (checkBox1->Checked)
{
serialPort1->Open();
}
else
{
serialPort1->Close();
}
}
Also I suggest to set the "read theresehold" to 4...
serialPort1->ReceivedBytesThreshold = 4;