datagridview排序以后，顺序错乱了

Question

http://download.csdn.net/detail/happs/4562932
这个程序里。。运行以后点击btn1，以及进行Changed排序之后点击btn1所呈现的结果
求解~~

Answer 1

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;namespace WindowsFormsDGV
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }        private void Form1_Load(object sender, EventArgs e)
        {
            bin();
        }
        private void bin()
        {
            DataTable table = GetData();
            this.dataGridView1.AutoGenerateColumns = false;
            this.dataGridView1.DataSource = table;
        }
        private DataTable GetData()
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("a", typeof(string));
            dt.Columns.Add("b", typeof(string));
            dt.Columns.Add("c", typeof(string));
            dt.Columns.Add("d", typeof(string));
            dt.Columns.Add("e", typeof(string));
            dt.Columns.Add("DZ",typeof (int));
            dt.Columns.Add("Changed", typeof(string));
            for (int i = 0; i < 5; i++)
            {
                DataRow row = dt.NewRow();
                row["a"] = (i + 1).ToString();
                row["b"] = (i + 1).ToString();
                row["c"] = (i + 1).ToString();
                row["d"] = (i + 1).ToString();
                row["e"] = (i + 1).ToString();
                row["DZ"] =i;
                row["Changed"] = DBNull.Value;
                dt.Rows.Add(row);
            }
            return dt;
        }
        private void button1_Click(object sender, EventArgs e)
        {
            for (int i = 0; i < dataGridView1.Rows.Count; i++)
            {
                dataGridView1.Rows[i].Cells["Changed"].Value = DBNull.Value;
                if (Convert.ToString(dataGridView1.Rows[i].Cells["DZ"].Value) == "1")
                {
                    dataGridView1.Rows[i].Cells["Changed"].Value = "1Changed";
                }
                else if (Convert.ToString(dataGridView1.Rows[i].Cells["DZ"].Value) == "3")
                {
                    dataGridView1.Rows[i].Cells["Changed"].Value = "3Changed";
                }
            }
        }
    }
}