progressBar刷新问题？

[zengbingling]

public partial class Form1 : Form
{
Worker worker;
object itemSycn;
public Form1()
{
InitializeComponent();
worker = new Worker(new EventHandler(worker_activedThreadChanged）;
}

private void btnRun_Click(object sender, EventArgs e)
{
progressBar1.Maximum = 100;
progressBar1.Value = 0;
worker.Work();
}

void worker_activedThreadChanged(object sender, EventArgs e)
{
progressBar1.Increment(1);
}
}
public class Worker
{
SimpleThreadPool threadPool;
EventHandler activedThreadChanged;
public Worker(EventHandler threadChagned)
{
threadPool = new SimpleThreadPool();
this.activedThreadChanged=threadChagned;
threadPool.ThreadCountChanged += new EventHandler(threadPool_ThreadCountChanged);
}
void threadPool_ThreadCountChanged(object sender, EventArgs e)
{
if (activedThreadChanged != null)
activedThreadChanged(sender, e);
}
void Work()
{
//执行线程池任务。一个任务完成时会执行threadPool_ThreadCountChanged。
}
}

问题：当执行完一个任务时，进度条数值变了但界面不刷新。执行完所有任务才显示进度完成?

[636f6c696e]

请在threadPool_ThreadCountChanged里，强制刷新progressbar
progressBar1.Refresh();

[pcqpzq]

后台线程不要直接更改UI，请用Form1.Invoke()方法，具体百度