C# 5.0 使用任务调试表TaskScheduler来运行task

示例效果与winform中this.invoke(new delegete{})跨线程操作资源类似

建立WPF项目，使用4.5框架

mainwindow.xml文件如下

<Window x:Class="TaskSchedulerDemo.MainWindow"        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"        xmlns:local="clr-namespace:TaskSchedulerDemo"        mc:Ignorable="d"        Title="MainWindow" Height="350" Width="525">    <Grid>        <TextBlock Name="ContentTextBlock" HorizontalAlignment="Left" Margin="44,134,0,0" VerticalAlignment="Top" Width="425" Height="40" />        <Button Content="Sync" HorizontalAlignment="Left" Margin="45,190,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click" />        <Button Content="Async" HorizontalAlignment="Left" Margin="165,190, 0, 0" VerticalAlignment="Top" Width="75" Click="Button_Click_1" />        <Button Content="Async OK" HorizontalAlignment="Left" Margin="285,190,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click_2" />    </Grid></Window>

mainwindow.xml.cs文件如下

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Navigation;using System.Windows.Shapes;using System.Threading;using System.Threading.Tasks;namespace TaskSchedulerDemo{    /// <summary>    /// MainWindow.xaml 的交互逻辑    /// </summary>    public partial class MainWindow : Window    {        public MainWindow()        {            InitializeComponent();        }        private void Button_Click(object sender, RoutedEventArgs e)        {            //同步运行任务，此时窗体将不作任何响应            ContentTextBlock.Text = string.Empty;            try            {                string result = TaskMethod().Result;                ContentTextBlock.Text = result;            }            catch(Exception ex)            {                ContentTextBlock.Text = ex.InnerException.Message;            }        }        private void Button_Click_1(object sender, RoutedEventArgs e)        {            //异步方式运行任务，窗体可被移动，但抛出子线程访问主线程资源异常            //但此种方式将存在异常的风险            ContentTextBlock.Text = string.Empty;            Mouse.OverrideCursor = Cursors.Wait;            Task<string> task = TaskMethod();            task.ContinueWith(t =>            {                ContentTextBlock.Text = t.Exception.InnerException.Message;                Mouse.OverrideCursor = null;            },             CancellationToken.None,             TaskContinuationOptions.OnlyOnFaulted,            TaskScheduler.FromCurrentSynchronizationContext());                   }        private void Button_Click_2(object sender, RoutedEventArgs e)        {            //异步方式运行任务，窗体可被移动，子线程可访问主线程资源            ContentTextBlock.Text = string.Empty;            Mouse.OverrideCursor = Cursors.Wait;            //区别在这            Task<string> task = TaskMethod(TaskScheduler.FromCurrentSynchronizationContext());            task.ContinueWith(t =>            {                Mouse.OverrideCursor = null;            },            CancellationToken.None,            TaskContinuationOptions.None,            TaskScheduler.FromCurrentSynchronizationContext());        }        Task<string> TaskMethod()        {            return TaskMethod(TaskScheduler.Default);        }        Task<string> TaskMethod(TaskScheduler scheduler)        {            //采用task延迟方式可中断延迟，而thread.sleep()则不能            //await Task.Delay(TimeSpan.FromSeconds(5), cancellationTokenSource.Token);            Task delay = Task.Delay(TimeSpan.FromSeconds(5));            return delay.ContinueWith(t =>            {                string str = string.Format("task is running on a thread id {0}. is thread pool thread: {1}",                Thread.CurrentThread.ManagedThreadId,                Thread.CurrentThread.IsThreadPoolThread);                // ContentTextBlock为主线程资源                ContentTextBlock.Text = str;                return str;            }, scheduler);        }    }}

运行如下：

注意异常提示的区别，中文为程序运行产生，英文为计划输出