1、首先我们要实现如下图的效果:
a、主线程A运行方法段1时创建子线程B
b、然后子线程B执行方法段2
c、执行完后通知主线程A执行方法段3
2、实现代码如下:
public Form1()
{
InitializeComponent();
} public void Method1()
{
//给主线程取个名字
if (Thread.CurrentThread.Name == null)
Thread.CurrentThread.Name = "main"; //获取主线程上下文
asyncOperation = AsyncOperationManager.CreateOperation(null); //创建一个线程并执行方法2
ThreadStart ts = new ThreadStart(Method2);
Thread t = new Thread(ts);
t.Name = "work";
t.Start();
} public void Method2()
{
MessageBox.Show("当前线程:" + Thread.CurrentThread.Name); //模拟干了一件3秒耗时的事情
Thread.Sleep(); //通知主线程我事情干好了,你可以执行方法3了
if (asyncOperation != null)
asyncOperation.Post(new SendOrPostCallback(Method3), null); //结束上下文的生存期
asyncOperation.OperationCompleted();
} public void Method3(object data)
{
MessageBox.Show("当前线程:" + Thread.CurrentThread.Name);
} private AsyncOperation asyncOperation;
private void button1_Click(object sender, EventArgs e)
{
Method1();
}
3、要点记录
1、AsyncOperation 一般通过 AsyncOperationManager 对象获取
asyncOperation = AsyncOperationManager.CreateOperation(null);
2、在System.Windows.Forms.Form的UI线程存在对应的上下文AsyncOperation,在Conosol控制台程序的主线程不存在上下文AsyncOperation
给个例子一看就清楚了
static AsyncOperation asyncOperation; static void Main(string[] args)
{
Console.WriteLine("我是主线程:" + Thread.CurrentThread.ManagedThreadId);
Method1();
Console.ReadKey();
} static void Method1()
{ //获取主线程上下文
asyncOperation = AsyncOperationManager.CreateOperation(null); //创建一个线程
ThreadStart ts = new ThreadStart(Method2);
Thread t = new Thread(ts);
t.Start();
} static void Method2()
{
Console.WriteLine("我是子线程:" + Thread.CurrentThread.ManagedThreadId); //模拟干了一件3秒耗时的事情
Thread.Sleep(); //通知主线程事情干好了,其实这里创建了一个新线程
if (asyncOperation != null)
asyncOperation.Post(new SendOrPostCallback(Method3), null); //结束上下文的生存期
asyncOperation.OperationCompleted();
} static void Method3(object data)
{
Console.WriteLine("我是上下文创建的线程:" + Thread.CurrentThread.ManagedThreadId);
}