使用案例
static void Main(string[] args)
{
Task t = new Task(() =>
{
Console.WriteLine("任务开始工作……");
//模拟工作过程
Thread.Sleep(5000);
});
t.Start();
t.ContinueWith((task) =>
{
Console.WriteLine("任务完成，完成时候的状态为：");
Console.WriteLine("IsCanceled={0}\tIsCompleted={1}\tIsFaulted={2}",
task.IsCanceled, task.IsCompleted, task.IsFaulted);
});
Console.ReadKey();
}
无返回值使用方式总结
- Start方式启动
var t1 = new Task(() => TaskMethod("Task 1"));
t1.Start();
Task.WaitAll(t1);//等待所有任务结束
- Run方式启动
Task.Run(() => TaskMethod("Task 2"));
- Factory方式启动
Task.Factory.StartNew(() => TaskMethod("Task 3")); //直接异步的方法
//或者
var t3=Task.Factory.StartNew(() => TaskMethod("Task 3"));
Task.WaitAll(t3);//等待所有任务结束
- 综合示例
static void Main(string[] args)
{
var t1 = new Task(() => TaskMethod("Task 1"));
var t2 = new Task(() => TaskMethod("Task 2"));
t2.Start();
t1.Start();
Task.WaitAll(t1, t2);
Task.Run(() => TaskMethod("Task 3"));
Task.Factory.StartNew(() => TaskMethod("Task 4"));
//标记为长时间运行任务,则任务不会使用线程池,而在单独的线程中运行。
Task.Factory.StartNew(() => TaskMethod("Task 5"), TaskCreationOptions.LongRunning);
#region 常规的使用方式
Console.WriteLine("主线程执行业务处理.");
//创建任务
Task task = new Task(() =>
{
Console.WriteLine("使用`System.Threading.Tasks.Task`执行异步操作.");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(i);
}
});
//启动任务,并安排到当前任务队列线程中执行任务(System.Threading.Tasks.TaskScheduler)
task.Start();
Console.WriteLine("主线程执行其他处理");
task.Wait();
#endregion
Thread.Sleep(TimeSpan.FromSeconds(1));
Console.ReadLine();
}
static void TaskMethod(string name)
{
Console.WriteLine("Task {0} is running on a thread id {1}. Is thread pool thread: {2}",
name, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread);
}
- 使用async/await的实现方式
using System;
using System.Threading;
using System.Threading.Tasks;
namespace ConsoleApp1
{
class Program
{
async static void AsyncFunction()
{
await Task.Delay(1);
Console.WriteLine("使用`System.Threading.Tasks.Task`执行异步操作.");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(string.Format("AsyncFunction:i={0}", i));
}
}
public static void Main()
{
Console.WriteLine("主线程执行业务处理.");
AsyncFunction();
Console.WriteLine("主线程执行其他处理");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(string.Format("Main:i={0}", i));
}
Console.ReadLine();
}
}
}
有返回值使用方式
Task<int> task = CreateTask("Task 1");
task.Start();
int result = task.Result;
- 有返回值综合使用范例
using System;
using System.Threading;
using System.Threading.Tasks;
namespace ConsoleApp1
{
class Program
{
static Task<int> CreateTask(string name)
{
return new Task<int>(() => TaskMethod(name));
}
static void Main(string[] args)
{
TaskMethod("Main Thread Task");
Task<int> task = CreateTask("Task 1");
task.Start();
int result = task.Result;
Console.WriteLine("Task 1 Result is: {0}", result);
task = CreateTask("Task 2");
task.RunSynchronously(); //该任务会运行在主线程中
result = task.Result;
Console.WriteLine("Task 2 Result is: {0}", result);
task = CreateTask("Task 3");
Console.WriteLine(task.Status);
task.Start();
while (!task.IsCompleted)
{
Console.WriteLine(task.Status);
Thread.Sleep(TimeSpan.FromSeconds(0.5));
}
Console.WriteLine(task.Status);
result = task.Result;
Console.WriteLine("Task 3 Result is: {0}", result);
#region 常规使用方式
//创建任务
Task<int> getsumtask = new Task<int>(() => Getsum());
//启动任务,并安排到当前任务队列线程中执行任务(System.Threading.Tasks.TaskScheduler)
getsumtask.Start();
Console.WriteLine("主线程执行其他处理");
getsumtask.Wait(); //等待任务的完成执行过程
Console.WriteLine("任务执行结果：{0}", getsumtask.Result.ToString());//获得任务的执行结果
#endregion
}
static int TaskMethod(string name)
{
Console.WriteLine("Task {0} is running on a thread id {1}. Is thread pool thread: {2}",
name, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread);
Thread.Sleep(TimeSpan.FromSeconds(2));
return 42;
}
static int Getsum()
{
int sum = 0;
Console.WriteLine("使用`Task`执行异步操作.");
for (int i = 0; i < 100; i++)
{
sum += i;
}
return sum;
}
}
}
- 注意的是，使用返回值时通常是需要等待子线程执行结果的情况，会堵塞主线程
using System;
using System.Threading.Tasks;
namespace ConsoleApp1
{
class Program
{
public static void Main()
{
var ret1 = AsyncGetsum();
Console.WriteLine("主线程执行其他处理");
for (int i = 1; i <= 3; i++)
Console.WriteLine("Call Main()");
int result = ret1.Result; //阻塞主线程
Console.WriteLine("任务执行结果：{0}", result);
}
async static Task<int> AsyncGetsum()
{
await Task.Delay(1);
int sum = 0;
Console.WriteLine("使用`Task`执行异步操作.");
for (int i = 0; i < 100; i++)
{
sum += i;
}
return sum;
}
}
}
简单总结：有async Task修饰的方法，方法里面必然有await的调用或者有Task相关的效用。在外部可以直接调用async修饰的方法。在Addressables中大量使用了Task的异步操作，所以也可以使用await来让异步操作以等待的方式运行, await能让Addressables的使用更加方便，少了很多回调相关逻辑的编写。
可以参照：https://www.jianshu.com/p/dfa98f540673
参考：
https://www.cnblogs.com/zhaoshujie/p/11082753.html
https://blog.csdn.net/kingBook928/article/details/104958881?spm=1001.2101.3001.6650.1&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-1.pc_relevant_default&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-1.pc_relevant_default&utm_relevant_index=2
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