Delphi Cookbook - Third Edition

How it works...

The btnStart event creates 10 threads and puts each of them in a simple generic list declared as TObjectList<TFileWriterThread>. This list will be used to iterate over the threads when terminating or checking the status of threads. Threads are not configured with FreeOnTerminate, because we require a live reference to check their status.

The real work is done in the Execute method of TFileWriterThread. Let's check it out:

procedure TFileWriterThread.Execute; 
var 
  I: Integer; 
  NumLines: Integer; 
begin 
  inherited; 
  //decide how many numbers to write 
  NumLines := 11 + Random(50); 
  for I := 1 to NumLines do 
  begin //wait a bit of time to simulate a higher workload TThread.Sleep(200); //acquire the lock on FStreamWriter. TMonitor.Enter(FStreamWriter); ...