c#开发一个“记事本”程序,要求能够实现文件的新建、打开、编辑、保存功能

本文介绍了一个简单的记事本程序开发过程,包括如何利用C#实现文件的新建、打开、编辑与保存等功能。通过使用FolderBrowserDialog进行文件夹选择,OpenFileDialog与SaveFileDialog进行文件对话框操作,程序实现了基本的文字处理功能。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

开发一个“记事本”程序,要求能够实现文件的新建、打开、编辑、保存功能

(注意:资源的释放,可以使用OpenFileDialogSaveFileDialog控件或者类)


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;

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

        private void button1_Click(object sender, EventArgs e)
        {
            FolderBrowserDialog folder = new FolderBrowserDialog();
            folder.ShowDialog();
            string path = folder.SelectedPath;
            string name = "\\" + "aa.txt";
            if (!File.Exists(path + name))
            {
                FileStream fs1 = new FileStream(path + name, FileMode.Create, FileAccess.Write);
                StreamWriter sw = new StreamWriter(fs1);
                MessageBox.Show("创建成功!");
                sw.Close();
                fs1.Close();
               
            }
            }

        private void button2_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Title = "打开(Open)";
            ofd.FileName = "";
            ofd.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);//为了获取特定的系统文件夹,可以使用System.Environment类的静态方法GetFolderPath()。该方法接受一个Environment.SpecialFolder枚举,其中可以定义要返回路径的哪个系统目录
            ofd.Filter = "文本文件(*.txt)|*.txt";
            ofd.ValidateNames = true;     //文件有效性验证ValidateNames,验证用户输入是否是一个有效的Windows文件名
            ofd.CheckFileExists = true;  //验证路径有效性
            ofd.CheckPathExists = true; //验证文件有效性
            try
            {
                if (ofd.ShowDialog() == DialogResult.OK)
                {
                    StreamReader sr = new StreamReader(ofd.FileName, System.Text.Encoding.Default);
                    this.richTextBox1.Text = sr.ReadToEnd();
                    
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        
        }
        private void openFileDialog2_FileOk(object sender, CancelEventArgs e)
        {

        }

        private void openFileDialog1_FileOk(object sender, CancelEventArgs e)
        {

        }

        public void richTextBox1_TextChanged(object sender, EventArgs e)
        {

        }

        private void button4_Click(object sender, EventArgs e)
        {
            SaveFileDialog saveFileDialog1 = new SaveFileDialog();
            saveFileDialog1.InitialDirectory = "d:\\";
            saveFileDialog1.Filter = "ext files (*.txt)|*.txt|All files(*.*)|*>**";
            saveFileDialog1.FilterIndex = 2;
            saveFileDialog1.RestoreDirectory = true;
            DialogResult dr = saveFileDialog1.ShowDialog();
            if (dr == DialogResult.OK && saveFileDialog1.FileName.Length > 0)
            {
                richTextBox1.SaveFile(saveFileDialog1.FileName, RichTextBoxStreamType.PlainText);
                MessageBox.Show("存储文件成功!", "保存文件");
            }
        }
        }
    }

新建txt文件


import java.awt.BorderLayout; import java.awt.Container; import java.awt.Font; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.InputEvent; import java.awt.event.KeyAdapter; import java.awt.event.KeyEvent; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.File; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import javax.swing.BorderFactory; import javax.swing.JFileChooser; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JOptionPane; import javax.swing.JPopupMenu; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.KeyStroke; import javax.swing.ScrollPaneConstants; import javax.swing.SwingConstants; public class JNotePadUI extends JFrame { private JMenuItem menuOpen; private JMenuItem menuSave; private JMenuItem menuSaveAs; private JMenuItem menuClose; private JMenu editMenu; private JMenuItem menuCut; private JMenuItem menuCopy; private JMenuItem menuPaste; private JMenuItem menuAbout; private JTextArea textArea; private JLabel stateBar; private JFileChooser fileChooser; private JPopupMenu popUpMenu; public JNotePadUI() { super("新建文本文件"); setUpUIComponent(); setUpEventListener(); setVisible(true); } private void setUpUIComponent() { setSize(640, 480); // 菜单栏 JMenuBar menuBar = new JMenuBar(); // 设置「文件」菜单 JMenu fileMenu = new JMenu("文件"); menuOpen = new JMenuItem("打开"); // 快捷键设置 menuOpen.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_O, InputEvent.CTRL_MASK)); menuSave = new JMenuItem("保存"); menuSave.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_S, InputEvent.CTRL_MASK)); menuSaveAs = new JMenuItem("另存为"); menuClose = new JMenuItem("关闭"); menuClose.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_Q, InputEvent.CTRL_MASK)); fileMenu.add(menuOpen); fileMenu.addSeparator(); // 分隔线 fileMenu.add(menuSave); fileMenu.add(menuSaveAs); fileMenu.addSeparator(); // 分隔线 fileMenu.add(menuClose); // 设置「编辑」菜单 JMenu editMenu = new JMenu("编辑"); menuCut = new JMenuItem("剪切"); menuCut.setAccelerator( KeyStroke.getKeyStroke(KeyEvent.VK_X, InputEvent.CTRL_MASK)); menuCopy = new JMenuItem("复制"); menuCopy.setAccelerator( KeyStroke.getKeyStroke(KeyEvent.VK_C, InputEvent.CTRL_MASK)); menuPaste = new JMenuItem("粘贴"); menuPaste.setAccelerator( KeyStroke.getKeyStroke(KeyEvent.VK_V, InputEvent.CTRL_MASK)); editMenu.add(menuCut); editMenu.add(menuCopy); editMenu.add(menuPaste); // 设置「关于」菜单 JMenu aboutMenu = new JMenu("关于"); menuAbout = new JMenuItem("关于JNotePad"); aboutMenu.add(menuAbout); menuBar.add(fileMenu); menuBar.add(editMenu); menuBar.add(aboutMenu); setJMenuBar(menuBar); // 文字编辑区域 textArea = new JTextArea(); textArea.setFont(new Font("宋体", Font.PLAIN, 16)); textArea.setLineWrap(true); JScrollPane panel = new JScrollPane(textArea, ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER); Container contentPane = getContentPane(); contentPane.add(panel, BorderLayout.CENTER); // 状态栏 stateBar = new JLabel("未修改"); stateBar.setHorizontalAlignment(SwingConstants.LEFT); stateBar.setBorder( BorderFactory.createEtchedBorder()); contentPane.add(stateBar, BorderLayout.SOUTH); popUpMenu = editMenu.getPopupMenu(); fileChooser = new JFileChooser(); } private void setUpEventListener() { // 按下窗口关闭钮事件处理 addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent e) { closeFile(); } } ); // 菜单 - 打开 menuOpen.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { openFile(); } } ); // 菜单 - 保存 menuSave.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { saveFile(); } } ); // 菜单 - 另存为 menuSaveAs.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { saveFileAs(); } } ); // 菜单 - 关闭文件 menuClose.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { closeFile(); } } ); // 菜单 - 剪切 menuCut.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { cut(); } } ); // 菜单 - 复制 menuCopy.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { copy(); } } ); // 菜单 - 粘贴 menuPaste.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { paste(); } } ); // 菜单 - 关于 menuAbout.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { // 显示对话框 JOptionPane.showOptionDialog(null, "程序名称:\n JNotePad \n" + "程序设计:\n \n" + "简介:\n 一个简单的文字编辑器\n" + " 可作为验收Java的实现对象\n" + " 欢迎网友下载研究交流\n\n" + " /", "关于JNotePad", JOptionPane.DEFAULT_OPTION, JOptionPane.INFORMATION_MESSAGE, null, null, null); } } ); // 编辑区键盘事件 textArea.addKeyListener( new KeyAdapter() { public void keyTyped(KeyEvent e) { processTextArea(); } } ); // 编辑区鼠标事件 textArea.addMouseListener( new MouseAdapter() { public void mouseReleased(MouseEvent e) { if(e.getButton() == MouseEvent.BUTTON3) popUpMenu.show(editMenu, e.getX(), e.getY()); } public void mouseClicked(MouseEvent e) { if(e.getButton() == MouseEvent.BUTTON1) popUpMenu.setVisible(false); } } ); } private void openFile() { if(isCurrentFileSaved()) { // 文件是否为保存状态 open(); // 打开 } else { // 显示对话框 int option = JOptionPane.showConfirmDialog( null, "文件已修改,是否保存?", "保存文件?", JOptionPane.YES_NO_OPTION, JOptionPane.WARNING_MESSAGE, null); switch(option) { // 确认文件保存 case JOptionPane.YES_OPTION: saveFile(); // 保存文件 break; // 放弃文件保存 case JOptionPane.NO_OPTION: open(); break; } } } private boolean isCurrentFileSaved() { if(stateBar.getText().equals("未修改")) { return false; } else { return true; } } private void open() { // fileChooser 是 JFileChooser 的实例 // 显示文件选取的对话框 int option = fileChooser.showDialog(null, null); // 使用者按下确认键 if(option == JFileChooser.APPROVE_OPTION) { try { // 开启选取的文件 BufferedReader buf = new BufferedReader( new FileReader( fileChooser.getSelectedFile())); // 设定文件标题 setTitle(fileChooser.getSelectedFile().toString()); // 清除前一次文件 textArea.setText(""); // 设定状态栏 stateBar.setText("未修改"); // 取得系统相依的换行字符 String lineSeparator = System.getProperty("line.separator"); // 读取文件并附加至文字编辑区 String text; while((text = buf.readLine()) != null) { textArea.append(text); textArea.append(lineSeparator); } buf.close(); } catch(IOException e) { JOptionPane.showMessageDialog(null, e.toString(), "开启文件失败", JOptionPane.ERROR_MESSAGE); } } } private void saveFile() { // 从标题栏取得文件名称 File file = new File(getTitle()); // 若指定的文件不存在 if(!file.exists()) { // 执行另存为 saveFileAs(); } else { try { // 开启指定的文件 BufferedWriter buf = new BufferedWriter( new FileWriter(file)); // 将文字编辑区的文字写入文件 buf.write(textArea.getText()); buf.close(); // 设定状态栏为未修改 stateBar.setText("未修改"); } catch(IOException e) { JOptionPane.showMessageDialog(null, e.toString(), "写入文件失败", JOptionPane.ERROR_MESSAGE); } } } private void saveFileAs() { // 显示文件对话框 int option = fileChooser.showSaveDialog(null); // 如果确认选取文件 if(option == JFileChooser.APPROVE_OPTION) { // 取得选择的文件 File file = fileChooser.getSelectedFile(); // 在标题栏上设定文件名称 setTitle(file.toString()); try { // 建立文件 file.createNewFile(); // 进行文件保存 saveFile(); } catch(IOException e) { JOptionPane.showMessageDialog(null, e.toString(), "无法建立新文件", JOptionPane.ERROR_MESSAGE); } } } private void closeFile() { // 是否已保存文件 if(isCurrentFileSaved()) { // 释放窗口资源,而后关闭程序 dispose(); } else { int option = JOptionPane.showConfirmDialog( null, "文件已修改,是否保存?", "保存文件?", JOptionPane.YES_NO_OPTION, JOptionPane.WARNING_MESSAGE, null); switch(option) { case JOptionPane.YES_OPTION: saveFile(); break; case JOptionPane.NO_OPTION: dispose(); } } } private void cut() { textArea.cut(); stateBar.setText("已修改"); popUpMenu.setVisible(false); } private void copy() { textArea.copy(); popUpMenu.setVisible(false); } private void paste() { textArea.paste(); stateBar.setText("已修改"); popUpMenu.setVisible(false); } private void processTextArea() { stateBar.setText("已修改"); } public static void main(String[] args) { new JNotePadUI(); } }
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值