//--------------------------- Sub-thread class ---------------------------------------
//------------------------------------------------------------------------------------
//---File:          clsSubThread
//---Description:   The sub-thread template class file
//---Author:        Knight
//------------------------------------------------------------------------------------
//---------------------------{Sub-thread class}---------------------------------------
namespace ThreadTemplate
{
using System;
using System.Threading;
using System.IO;
/// <summary>
/// Summary description for clsSubThread.
/// </summary>
public class clsSubThread:IDisposable
{
private Thread thdSubThread = null;
private Mutex mUnique = new Mutex();

private bool blnIsStopped;
private bool blnSuspended;
private bool blnStarted;
private int nStartNum;

public bool IsStopped
{
get{ return blnIsStopped; }
}
public bool IsSuspended
{
get{ return blnSuspended; }
}
public int ReturnValue
{
get{ return nStartNum;}
}

  
public clsSubThread( int StartNum )
{
//
// TODO: Add constructor logic here
//
blnIsStopped = true;
blnSuspended = false;
blnStarted = false;

nStartNum = StartNum;
}

/// <summary>
/// Start sub-thread
/// </summary>
public void Start()
{
if( !blnStarted )
{
thdSubThread = new Thread( new ThreadStart( SubThread ) );
blnIsStopped = false;
blnStarted = true;
thdSubThread.Start();
}
}

/// <summary>
/// Thread entry function
/// </summary>
private void SubThread()
{
do
{
// Wait for resume-command if got suspend-command here
mUnique.WaitOne();
mUnique.ReleaseMutex();

nStartNum++;

Thread.Sleep(1000); // Release CPU here
}while( blnIsStopped == false );
}

/// <summary>
/// Suspend sub-thread
/// </summary>
public void Suspend()
{
if( blnStarted && !blnSuspended )
{
blnSuspended = true;
mUnique.WaitOne();
}
}

/// <summary>
/// Resume sub-thread
/// </summary>
public void Resume()
{
if( blnStarted && blnSuspended )
{
blnSuspended = false;
mUnique.ReleaseMutex();
}
}

/// <summary>
/// Stop sub-thread
/// </summary>
public void Stop()
{
if( blnStarted )
{
if( blnSuspended )
Resume();

blnStarted = false;
blnIsStopped = true;
thdSubThread.Join();
}
}
#region IDisposable Members
/// <summary>
/// Class resources dispose here
/// </summary>
public void Dispose()
{
// TODO:  Add clsSubThread.Dispose implementation
Stop();//Stop thread first
GC.SuppressFinalize( this );
}

#endregion
}
}

那么對于調(diào)用呢，就非常簡單了，如下：
// Create new sub-thread object with parameters
clsSubThread mySubThread = new clsSubThread( 5 );

mySubThread.Start();//Start thread

Thread.Sleep( 2000 );
mySubThread.Suspend();//Suspend thread

Thread.Sleep( 2000 );
mySubThread.Resume();//Resume thread

Thread.Sleep( 2000 );
mySubThread.Stop();//Stop thread

//Get thread's return value
Debug.WriteLine( mySubThread.ReturnValue );

//Release sub-thread object
mySubThread.Dispose();

在回過頭來看看前面所說的三個(gè)問題。
對于問題一來說，首先需要局部成員的支持，那么
private Mutex mUnique = new Mutex();

private bool blnIsStopped;
private bool blnSuspended;
private bool blnStarted;

光看成員名稱，估計(jì)大家都已經(jīng)猜出其代表的意思。接下來需要修改線程入口函數(shù)，要是這些開關(guān)變量能發(fā)揮作用，那么看看SubThread這個(gè)函數(shù)。
/// <summary>
/// Thread entry function
/// </summary>
private void SubThread()
{
do
{
// Wait for resume-command if got suspend-command here
mUnique.WaitOne();
mUnique.ReleaseMutex();

nStartNum++;

Thread.Sleep(1000);
}while( blnIsStopped == false );
}

函數(shù)比較簡單，不到十句，可能對于“blnIsStopped == false”這個(gè)判斷來說，大家還比較好理解，這是一個(gè)普通的判斷，如果當(dāng)前Stop開關(guān)打開了，就停止循環(huán)；否則一直循環(huán)。
大家比較迷惑的可能是如下這兩句：
mUnique.WaitOne();
mUnique.ReleaseMutex();
這兩句的目的是為了使線程在Suspend操作的時(shí)候能發(fā)揮效果，為了解釋這兩句，需要結(jié)合Suspend和Resume這兩個(gè)方法，它倆的代碼如下。
/// <summary>
/// Suspend sub-thread
/// </summary>
public void Suspend()
{
if( blnStarted && !blnSuspended )
{
blnSuspended = true;
mUnique.WaitOne();
}
}

/// <summary>
/// Resume sub-thread
/// </summary>
public void Resume()
{
if( blnStarted && blnSuspended )
{
blnSuspended = false;
mUnique.ReleaseMutex();
}
}

mUnique.WaitOne();
mUnique.ReleaseMutex();