C# List生成Txt文档并且读取Txt文档封装List

using DictionaryToTxtFile;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.windows.FORMs;

namespace IC00520
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        public static Dao dao = new Dao();//调用方法的声明
        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog openFile = new OpenFileDialog();//定义打开文件类
            openFile.Filter = "Txt文件(*.Txt)|*.txt|所有文件|*.*";
            if (openFile.ShowDialog() != DialogResult.OK)//打开文件是否点击了取消
                return;
            string path = openFile.FileName;//获得你打开文件的名称，路径
            List<int> datalist= dao.WriteData(path);//调用方法
            foreach(int i in datalist)//遍历展示数据
            {
                richTextBox1.Text += i.ToString()+"\r\n";
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            List<int> list = new List<int>();
            for(int i = 0; i<100;i++)//生成100个虚拟数据测试
            {
                list.Add(i);
            }
            dao.SaveData(list, "C:\Users\ASUS\source\repos\IC00520\IC00520\");//将数据和文件路径作为实参
        }
    }
}

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DictionaryToTxtFile
{
    public class Dao
    {
        public string SaveData(List<int> info,string path)
        {
            try
            {
                string dataName = "";//数据下发文件名
                string Data = "";
                foreach (var item in info)//遍历List数据将数据保存在Data中
                {
                    Data += item + "\r\n";
                }
                dataName = "IC00" + DateTime.Now.ToString("yyyy_MM_dd HH_mm_ss")+ ".txt";//以日期创建文件名
                path += dataName;
                File.AppendAllText(path, Data);//直接追加，如果没有这个文件会自动添加
                return "OK";
            }
           catch(Exception ex)
            {
                return ex.Message.ToString();
            } 
        }
        public List<int>  WriteData(string filepath)
        {
            try
            {
                List<int> info = new List<int>();
                string[] lines = File.ReadAllLines(filepath);//读取文件中的所有行并将所有行放进string数组中
                for (int i = 0; i < lines.Length; i ++)
                {
                    int value = int.Parse(lines[i]);//遍历赋值，返回list的值
                    info.Add(value);
                }
                return info;
            }
           catch(Exception ex)
            {
                return null;
            }
        }
    }
}