1、基於流的文字檔案的讀寫對於C#來說比較簡單，通常來講，需要以下5個基本步驟：

1. 建立一個檔案流——FileStream
2. 建立讀取器或寫入器——StreamReader/StreamWriter
3. 執行讀或者寫操作
4. 關閉讀取器或寫入器
5. 關閉檔案流

2、BinaryReader和BinaryWriter類可用於讀寫二進位制檔案 這兩個類並不派生於Stream，而是直接派生於System.Object類 所有建立兩個類的物件必須基於所提供的派生於Stream類的物件，如FileStream類的物件

3、File類和FileInfo類——檔案基本操作 Directory類和DirectoryInfo類——目錄基本操作 Path類和Enviroment類——路徑類和系統資訊類

4、當要讀取的檔案中包含漢字，需要指定編碼Encoding.GetEncoding(“GB2312”) string[ ] content=File.ReadAllLines(path，Encoding.GetEncoding(“GB2312”))；

5、讀寫文字檔案

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;
using System.IO;
using System.Text;

namespace WindowsFormsApp4
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void btnRead_Click(object sender, EventArgs e)
        {
            if (ofdOpen.ShowDialog() == DialogResult.OK)
            {
                string filePath = ofdOpen.FileName;
                txtFilePath.Text = filePath;

                if (File.Exists(filePath))
                {
                    StreamReader sr = new StreamReader(filePath, Encoding.GetEncoding("gb2312"));
                    string input;
                    while ((input = sr.ReadLine()) != null)
                    {
                        txtFileContent.Text += input + "\r\n";
                    }
                    sr.Close();
                }
                else
                {
                    MessageBox.Show("您要讀取的檔案不存在！");
                }
            }
        }

        private void btnWrite_Click(object sender, EventArgs e)
        {
            sfdSave.Filter = "文字檔案(*.txt)|*.txt";
            if (sfdSave.ShowDialog() == DialogResult.OK)
            {
                string filePath = sfdSave.FileName;
                StreamWriter sw = new StreamWriter(filePath, false);
                sw.WriteLine(txtFileContent.Text);
                sw.Close();
            }
        }
    }
}

 

6、檔案基本操作

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;
using System.IO;
using Microsoft.VisualBasic.Devices;

namespace WindowsFormsApp3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void label1_Click(object sender, EventArgs e)
        {

        }

        private void btnCreate_Click(object sender, EventArgs e)
        {
            string path = @txtFile.Text;
            if (File.Exists(path))
                MessageBox.Show("檔名已存在");
            try
            {
                using(StreamWriter sw = File.CreateText(path))
                {
                    sw.WriteLine("不想說話");
                    sw.WriteLine("");
                    sw.WriteLine("建立日期時間"+DateTime.Now.ToString());
                    sw.Flush();
                    MessageBox.Show("檔案建立成功！");
                }
            }
            catch(Exception ex)
            {
                MessageBox.Show("檔案無法建立。" + Environment.NewLine + "請確認檔名稱是否正確," + "以及您是否擁有建立許可權。");
            }
        }

        private void btnCopy_Click(object sender, EventArgs e)
        {
            try
            {
                File.Copy(@"d:\t87.txt", @"d:\t87_1.txt", true);
                FileInfo fi = new FileInfo(@"d:\t87.txt");
                fi.CopyTo(@"d:\t87_2.txt", true);
                MessageBox.Show("檔案已複製");
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message);
                return;
            }
        }

        private void btnRename_Click(object sender, EventArgs e)
        {
            try
            {
                Computer MyComputer = new Computer();
               // File.Copy(@"d:\t87.text", @"d:\t87_3.text", true);
                MyComputer.FileSystem.RenameFile(@"d:\t87.txt", "更改檔名.txt");
                MessageBox.Show("更改檔名成功！");
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return;
            }
        }

        private void btnMove_Click(object sender, EventArgs e)
        {
           if(File.Exists(@"d:\t87.txt")){

                //檔案被執行緒佔用，不能移動，解決方法可以重新Copy一個移動
                File.Copy(@"d:\t87.txt", @"d:\移動.txt",true);
                File.Move(@"d:\移動.txt", @"d:\移動1.txt");
                MessageBox.Show("檔案移動成功！");
            }
            else
            {
                FileInfo fi = new FileInfo(@"d:\t87.txt");
                StreamWriter sw = fi.CreateText();
                MessageBox.Show("移動前例項化檔案" + fi.Name);

                //檔案被執行緒佔用，不能移動
                fi.CopyTo(@"d:\移動2.txt");
                
            }
           
        }

        private void btnDelete_Click(object sender, EventArgs e)
        {
            try
            {
                if (File.Exists(@"d:\t87.txt"))
                    File.Delete(@"d:\t87.txt");
                else
                {
                    FileInfo fi = new FileInfo(@"d:\t87.txt");
                    StreamWriter sw = fi.CreateText();
                    MessageBox.Show("刪除前例項化檔案" + fi.Name);
                }

                MessageBox.Show("檔案刪除成功！");
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message);
                return;
            }
        }
    }
}