本文转自：http://dotnet.chinaitlab.com/CSharp/801729.html
背景
在用Windows Form编程时候，我们通常会遇到如此问题：
1. 后台更新大量处理数据过程。
2.需要把后台的Log输出到前端，以监控运行状态。
3. 如果运行大量处理过程，前端会出现白屏状态，这样对用户不友好。
针对此，我们需求创建多线程来处理后台。用多线程调用处理，按平常处理，是不能更新主线程的控件的，需要做特殊处理。
代码程序如下：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Threading;
namespace TestWinForm
{
public partial class Form1 : Form
{
delegate void SetValueCallback(int value);
public Form1()
{
InitializeComponent();
}
private void btnRun_Click(object sender, EventArgs e)
{
Thread t = new Thread(new ThreadStart(Foo));
t.Start();
}
private void Foo()
{
for (int i = 1; i <= 100; i++)
{
Thread.Sleep(100);
SetProcessBarValue(i);
SetLabelValue(i);
}
}
private void SetLabelValue(int value)
{
// InvokeRequired required compares the thread ID of the
// calling thread to the thread ID of the creating thread.
// If these threads are different, it returns true.
if (this.lblStatus.InvokeRequired)
{
SetValueCallback d = new SetValueCallback(SetLabelValue);
this.Invoke(d, new object[] { value });
}
else
{
this.lblStatus.Text = value.ToString()+'%';
}
}
private void SetProcessBarValue(int value)
{
// InvokeRequired required compares the thread ID of the
// calling thread to the thread ID of the creating thread.
// If these threads are different, it returns true.
if (this.prbStatus.InvokeRequired)
{
SetValueCallback d = new SetValueCallback(SetProcessBarValue);
this.Invoke(d, new object[] { value });
}
else
{
this.prbStatus.Value = value;
}
}
}
}