using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace CrossThreadsUpdateUIDemo
{
public partial class FrmMain : Form
{
/// <summary>
/// 任务队列
/// </summary>
private Queue<int> _queueTask = new Queue<int>();
/// <summary>
/// 任务循环执行次数
/// </summary>
private static int _executeCounter = 0;
private static object locker = new object();
public FrmMain()
{
InitializeComponent();
}
#region Methods
/// <summary>
/// 更新UI控件
/// </summary>
/// <param name="message"></param>
private void UpdateLogUI(string message)
{
BeginInvoke(new Action(() =>
{
lstLog.Items.Insert(0, message);
}));
}
/// <summary>
/// 模拟加载数据
/// </summary>
private void LoadData()
{
for (int i = 1; i <= 5; i++)
{
_queueTask.Enqueue(i);
}
}
#endregion
private async void btnStart_Click(object sender, EventArgs e)
{
var t = new Thread(new ThreadStart(() => { }));
t.IsBackground = true;
t.Start();
_executeCounter = 0;
//lstLog.Items.Clear();
LoadData();
do
{
if (_queueTask == null || _queueTask.Count <= 0)
{
break;
}
await Task.Run(() =>
{
try
{
var num = 0;
_executeCounter++;
UpdateLogUI(string.Format("开始第{0}次任务,总任务数:{1}...", _executeCounter, _queueTask == null ? 0 : _queueTask.Count));
var total = _queueTask.Count;
Parallel.For(0, total, new ParallelOptions { MaxDegreeOfParallelism = 3 }, t =>
{
if (num <= 3)
{
Thread.Sleep(500);
num++;
}
while (_queueTask.Count > 0)
{
var rand = new Random();
var sleep = rand.Next(500, 5000);
int task = 0;
if (_queueTask.Count > 0)
{
lock (_queueTask)
{
task = _queueTask.Dequeue();
}
}
UpdateLogUI(string.Format("Task {0} start,Sleep:{1}...", task, sleep));
Thread.Sleep(sleep);
UpdateLogUI(string.Format("Task {0} completed.", task));
}
});
}
catch (Exception ex)
{
UpdateLogUI(string.Format("错误:{0}", ex.Message));
}
}).ContinueWith(t =>
{
UpdateLogUI(string.Format("第{0}次任务执行完成.", _executeCounter));
if (_executeCounter < 5)
{
LoadData();
}
});
}
while (_queueTask.Count > 0);
UpdateLogUI("任务完毕");
}
}
}
