thread

代码说明：

  运行程序，单击“启动线程”按钮，程序将启动一个线程，线程将进行数值计算，并将结果发送给主窗口；单击“挂起线程”按钮，线程将挂起；单击“恢复线程”按钮，线程将恢复。(Run the program, click" start the thread" button, the program will start a thread, the thread will make numerical computation, and sends the result to the main window click" thread hang" button, the thread will be suspended click on" restore thread" button, the thread will recover.)