C#-APP: Blocking while waiting for an event

[AlexBecker]

Hi.

I'm coding a C# app and I need to block processing in order to wait for an event.
If I use Thread.Sleep() the event is never triggered so I don't know what else to do.

This is my code (well, pseudo, as I don't have access to it right now):

bool dataArrived;
byte[] data;
 
void EventReceiveData()
{
  data = //.. whatever
  dataArrived = true;
}
 
byte[] RequestX()
{
  dataArrived = false;
  SendData('X');
 
  while (!dataArrived)
    Thread.Sleep(10);
 
  Return data;
}

Any ideas?

Thank you in advance.
Alex

[balabaster]

Hi.

I'm coding a C# app and I need to block processing in order to wait for an event.
If I use Thread.Sleep() the event is never triggered so I don't know what else to do.

This is my code (well, pseudo, as I don't have access to it right now):

bool dataArrived;
byte[] data;
 
void EventReceiveData()
{
data = //.. whatever
dataArrived = true;
}
 
byte[] RequestX()
{
dataArrived = false;
SendData('X');
 
while (!dataArrived)
Thread.Sleep(10);
 
Return data;
}

Any ideas?

Thank you in advance.
Alex

I would use a ManualResetEvent (found in System.Threading). You would reset this before you fire your secondary thread and then use the WaitOne method to block the current thread. You would then have your secondary thread set the ManualResetEvent which would cause the main thread to continue.
VB

 'Classwide declaration: 
Dim oSignalEvent As New System.Threading.ManualResetEvent(False)
 
Private Sub SecondThread()
'Do stuff
oSignalEvent.Set()
End Sub
 
Private Sub MainThread()
    'Do stuff
    'Call secondary thread
 
    Dim oSecondThread As New System.Threading.Thread(AddressOf SecondThread)
    oSecondThread.Start()
 
    oSignalEvent.WaitOne() 'This thread will block here until the reset event is set.
    oSignalEvent.Reset() 'Set the signal back to false
    'Do more stuff
 
End Sub
 

C#

 ManualResetEvent oSignalEvent = New ManualResetEvent; 
void SecondThread(){
//DoStuff
oSignalEvent.Set();
}
void Main(){
//DoStuff
//Call second thread
System.Threading.Thread oSecondThread = new System.Threading.Thread(SecondThread);
oSecondThread.Start();
 
oSignalEvent.WaitOne(); //This thread will block here until the reset event is sent.
oSignalEvent.Reset();
//Do more stuff
}