c#线程创建

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 WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        Thread th;
        private void button1_Click(object sender, EventArgs e)
        {
          th = new Thread(test);
            th.IsBackground = true;
            th.Start();

        }

        private void test()
        {
            int n = 100000;
            this.textBox1.Text = Convert.ToString((1 + n) * n / 2);

        }

        private void Form1_Load(object sender, EventArgs e)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {

            if (th != null)
            {
                th.Abort();
            }
        }
    }
}