解決C#中txt文檔匯入資料庫時，中文顯示亂碼的問題

與前篇文章不同之處用紅筆標記

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.IO;
using System.Data.SqlClient;

namespace txt匯入至資料庫
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        public static System.Text.Encoding GetFileEncoding(string fileFullName)
        {
            FileStream fs = new FileStream(fileFullName, FileMode.Open, FileAccess.Read);
            System.Text.Encoding r = GetType(fs);
            fs.Close();
            return r;
        }

        public static System.Text.Encoding GetType(FileStream fs)
        {
            /*
             * byte[] Unicode=new byte[]{0xFF,0xFE}; 
             * byte[] UnicodeBIG=new byte[]{0xFE,0xFF}; 
             * byte[] UTF8=new byte[]{0xEF,0xBB,0xBF};
             */

            BinaryReader r = new BinaryReader(fs, System.Text.Encoding.Default);
            byte[] ss = r.ReadBytes(3);
            r.Close();
            //編碼類別型 Coding=編碼類別型.ASCII;  
            if (ss[0] >= 0xEF)
            {
                if (ss[0] == 0xEF && ss[1] == 0xBB && ss[2] == 0xBF)
                {
                    return System.Text.Encoding.UTF8;
                }
                else if (ss[0] == 0xFE && ss[1] == 0xFF)
                {
                    return System.Text.Encoding.BigEndianUnicode;
                }
                else if (ss[0] == 0xFF && ss[1] == 0xFE)
                {
                    return System.Text.Encoding.Unicode;
                }
                else
                {
                    return System.Text.Encoding.Default;
                }
            }
            else
            {
                return System.Text.Encoding.Default;
            }
        }
        private void button1_Click(object sender, EventArgs e)
        {
            if (ofdfile.ShowDialog() == DialogResult.OK)
            {
               using (FileStream fileStream=File.OpenRead(ofdfile.FileName))
               {
                  Encoding readEncoding = GetFileEncoding(ofdfile.FileName);

                 
                using (StreamReader streamreader = new StreamReader(fileStream,readEncoding))
                {
                   
                    using (SqlConnection conn = new SqlConnection("server=.;database=test;user id=sa;password=123456"))
                    {
                        conn.Open();
                        string lines = null;
                        using (SqlCommand cmd = conn.CreateCommand())
                        {
                            cmd.CommandText = "insert into T_persons(name,age)values(@name,@age)";
                          
                            while ((lines=streamreader.ReadLine()) != null)
                            {
                          
                                string[] strs = lines.Split('|');
                                string name = strs[0].ToString();
                                int age = Convert.ToInt32(strs[1]);
                                cmd.Parameters.Clear();
                                cmd.Parameters.Add(new SqlParameter("name",name));
                                cmd.Parameters.Add(new SqlParameter("age",age));
                                cmd.ExecuteNonQuery();
                               
                            }
                        }

                    }
                }
                }
               MessageBox.Show("資料匯入成功");

            }
        }
    }
}