public DicomState EndPrint(IAsyncResult ar)
{
PrintDelegate asyncDelegate = ((AsyncResult)ar).AsyncDelegate as PrintDelegate;
if (asyncDelegate == null)
{
throw new InvalidOperationException("cannot get results, asynchresult is null");
}
return(asyncDelegate.EndInvoke(ar));
}
static void Case1()
{
Console.WriteLine("main thread is started.");
PrintDelegate print = new PrintDelegate(Print);
IAsyncResult result = print.BeginInvoke("hello world.", null, null);
Console.WriteLine("main thread is going.");
print.EndInvoke(result);//EndInvode()负责一直阻塞当前线程，等待返回结果后继续执行
Console.WriteLine("compeleted.");
}
public static void Test()
{
PrintDelegate printDelegate = Print;
Console.WriteLine("主线程");
IAsyncResult result = printDelegate.BeginInvoke("Hello World.", null, null);
Console.WriteLine("主线程继续执行...");
//当使用BeginInvoke异步调用方法时，如果方法未执行完，
//EndInvoke方法就会一直阻塞，直到被调用的方法执行完毕
printDelegate.EndInvoke(result);
Console.WriteLine("Press any key to continue...");
Console.ReadKey(true);
}