情境: 最近用winform做一个小程序,主要是用来执行一些sql语句,无奈数据量太大,执行一次要二十分钟左右,执行期间界面根本不能再进行其它操作,就连最小化窗口都不行,一动就跟死机差不多了.
因此到网上搜了一下,找到.net后台线程的概念.(高手请绕道!)
前台线程和后台线程之间的选择
.NET Framework 中的所有线程都被指定为前台线程或后台线程。这两种线程唯一的区别是 — 后台线程不会阻止进程终止。在属于一个进程的所有前台线程终止之后,公共语言运行库 (CLR) 就会结束进程,从而终止仍在运行的任何后台线程。
在默认情况下,通过创建并启动新的 Thread 对象生成的所有线程都是前台线程,而从非托管代码进入托管执行环境中的所有线程都标记为后台线程。然而,通过修改 Thread.IsBackground 属性,可以指定一个线程是前台线程还是后台线程。通过将 Thread.IsBackground 设置为 true,可以将一个线程指定为后台线程;通过将 Thread.IsBackground 设置为 false,可以将一个线程指定为前台线程。
using System;
using System.Threading;
class Test
{
static void Main()
{
BackgroundTest shortTest = new BackgroundTest(10);
Thread foregroundThread =
new Thread(new ThreadStart(shortTest.RunLoop));
foregroundThread.Name = "ForegroundThread";
BackgroundTest longTest = new BackgroundTest(50);
Thread backgroundThread =
new Thread(new ThreadStart(longTest.RunLoop));
backgroundThread.Name = "BackgroundThread";
backgroundThread.IsBackground = true;
foregroundThread.Start();
backgroundThread.Start();
}
}
class BackgroundTest
{
int maxIterations;
public BackgroundTest(int maxIterations)
{
this.maxIterations = maxIterations;
}
public void RunLoop()
{
String threadName = Thread.CurrentThread.Name;
for(int i = 0; i < maxIterations; i++)
{
Console.WriteLine("{0} count: {1}",
threadName, i.ToString());
Thread.Sleep(250);
}
Console.WriteLine("{0} finished counting.", threadName);
}
}
using System.Threading;
class Test
{
static void Main()
{
BackgroundTest shortTest = new BackgroundTest(10);
Thread foregroundThread =
new Thread(new ThreadStart(shortTest.RunLoop));
foregroundThread.Name = "ForegroundThread";
BackgroundTest longTest = new BackgroundTest(50);
Thread backgroundThread =
new Thread(new ThreadStart(longTest.RunLoop));
backgroundThread.Name = "BackgroundThread";
backgroundThread.IsBackground = true;
foregroundThread.Start();
backgroundThread.Start();
}
}
class BackgroundTest
{
int maxIterations;
public BackgroundTest(int maxIterations)
{
this.maxIterations = maxIterations;
}
public void RunLoop()
{
String threadName = Thread.CurrentThread.Name;
for(int i = 0; i < maxIterations; i++)
{
Console.WriteLine("{0} count: {1}",
threadName, i.ToString());
Thread.Sleep(250);
}
Console.WriteLine("{0} finished counting.", threadName);
}
}