What is the quickest, least lines of code, way of creating a thread in ones code?
The answer is to create an anonymous delegate and pass it over to the ThreadPool object. Below is a class comically called DirtyPool which demonstrates these items:
- Self contained code, call the static ShowExample to run the console example.
- Uses three threads, two to generate data and one to write it out.
- Calls QueueUserWorkItem off of the ThreadPool to launch the threads.
- Demonstrates thread safe access to shared resource by using lock.
Here is the quick code example:
public class DirtyPool
{
// Data held in this queue.
public static Queue<string> _Operations
= new Queue<string>();
// Status objects for printer delegate/thred
// to know when to exit.
bool OneEnded;
bool TwoEnded;
public static void ShowExample()
{
DirtyPool dp = new DirtyPool();
dp.DoIt();
// Sleep long enough so not to kill the threads.
Thread.Sleep( 10000 );
}
public void SetData( string who )
{
lock ( _Operations )
_Operations.Enqueue( who );
}
public void PrintData( )
{
lock ( _Operations )
if (_Operations.Count > 0)
Console.WriteLine( _Operations.Dequeue() );
}
public void DoIt()
{
ThreadPool.QueueUserWorkItem(
delegate // Anonomous Delegate For Creation 1
{
for ( int index = 0; index < 5; ++index )
{
Thread.Sleep( 1500 );
SetData( "Pool 1: " + index );
}
OneEnded = true;
}
);
ThreadPool.QueueUserWorkItem(
delegate // Anonomous Delegate For Creation 2
{
for ( int index = 0; index < 5; ++index )
{
Thread.Sleep( 1000 );
SetData( "Pool 2: " + index );
}
TwoEnded = true;
}
);
ThreadPool.QueueUserWorkItem(
delegate // Anonomous Delegate For Extraction & Printing
{
while ( !( TwoEnded && OneEnded ) )
PrintData();
PrintData(); // Just in case...
}
);
}
}
Here is the output:
Pool 2: 0
Pool 1: 0
Pool 2: 1
Pool 1: 1
Pool 2: 2
Pool 2: 3
Pool 1: 2
Pool 2: 4
Pool 1: 3
Pool 1: 4
Press any key to continue . . .
