【Java】實現一個簡易記事本Notepad的編寫

文章目錄

• 記事本圖例
• 開啟圖例：
• 另存新檔圖例

記事本功能介紹1.   建立：記事本清空。2.   開啟：可開啟筆記本上任意文字檔。3.   儲存：將檔案儲存至當前檔案夾。4.   另存新檔：將檔案儲存至任意位置。5.   退出：退出時確認退出前是否儲存內容。【註：“儲存”和“另存新檔”時，應指明檔案的尾碼，如：XXX.txt】記事本圖例開啟筆記本上任意文字檔該操作需要用到  FileDialog 類 中的 FileDialog.LOAD);

FileDialog fd = new FileDialog(this, "開啟", FileDialog.LOAD);fd.setVisible(true);

值得注意的是，在擷取檔案路徑時，相關操作為：

String strFile = fd.getDirectory() + fd.getFile();

若沒有 fd.getDirectory()  則只能開啟當前檔案夾。fd.getDirectory()  相當於取得檔案的絕對路徑首碼。

取得路徑後，就可以將檔案開啟並寫到文字框中。具體操作見部落格：http://blog.csdn.net/oyuntaolianwu/article/details/9429953代碼舉例

private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:FileDialog fd = new FileDialog(this, "開啟", FileDialog.LOAD);fd.setVisible(true);String strFile = fd.getDirectory() + fd.getFile();if (strFile != null) {try {FileInputStream fis = new FileInputStream(strFile);byte[] buf = new byte[10 * 1024];int len = fis.read(buf);jTextArea1.append(new String(buf, 0, len));fis.close();} catch (Exception e) {System.out.println("開啟失敗");}}}

開啟圖例：將檔案儲存至任意位置實際上，與上述操作相仿。只不過，是一個讀一個寫。取得檔案路徑和內容後，相關操作就容易很多了。代碼舉例：

private void jMenuItem4ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:FileDialog fd = new FileDialog(this, "另存新檔", FileDialog.SAVE);fd.setVisible(true);String string1 = jTextArea1.getText();String stringfile = fd.getDirectory()+fd.getFile();BufferedWriter bWriter = null;try {bWriter = new BufferedWriter(new FileWriter(stringfile));bWriter.write(string1); bWriter.close(); } catch (Exception e) {// TODO Auto-generated catch blockSystem.out.println("儲存失敗");} }

另存新檔圖例記事本 NotePad  代碼

/* * Test_Notepad.java * * Created on __DATE__, __TIME__ *///package com.test;import java.awt.*;import java.io.*;import javax.swing.JOptionPane;/** * * @author  __USER__ */public class Test_Notepad extends javax.swing.JFrame {/** Creates new form Test_Notepad */public Test_Notepad(String name) {super(name);initComponents();setLocation(450, 200);}/** This method is called from within the constructor to * initialize the form. * WARNING: Do NOT modify this code. The content of this method is * always regenerated by the Form Editor. *///GEN-BEGIN:initComponents// <editor-fold defaultstate="collapsed" desc="Generated Code">private void initComponents() {jScrollPane1 = new javax.swing.JScrollPane();jTextArea1 = new javax.swing.JTextArea();jMenuBar1 = new javax.swing.JMenuBar();jMenu1 = new javax.swing.JMenu();jMenuItem1 = new javax.swing.JMenuItem();jMenuItem2 = new javax.swing.JMenuItem();jMenuItem3 = new javax.swing.JMenuItem();jMenuItem4 = new javax.swing.JMenuItem();jSeparator1 = new javax.swing.JSeparator();jSeparator2 = new javax.swing.JSeparator();jMenuItem6 = new javax.swing.JMenuItem();jMenu2 = new javax.swing.JMenu();jMenuItem7 = new javax.swing.JMenuItem();jMenuItem8 = new javax.swing.JMenuItem();jMenuItem9 = new javax.swing.JMenuItem();jMenuItem10 = new javax.swing.JMenuItem();jMenuItem11 = new javax.swing.JMenuItem();setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);jTextArea1.setColumns(20);jTextArea1.setRows(5);jScrollPane1.setViewportView(jTextArea1);jMenu1.setText("\u6587\u4ef6");jMenu1.setMinimumSize(new java.awt.Dimension(35, 19));jMenuItem1.setText("\u65b0\u5efa");jMenuItem1.addActionListener(new java.awt.event.ActionListener() {public void actionPerformed(java.awt.event.ActionEvent evt) {jMenuItem1ActionPerformed(evt);}});jMenu1.add(jMenuItem1);jMenuItem2.setText("\u6253\u5f00");jMenuItem2.addActionListener(new java.awt.event.ActionListener() {public void actionPerformed(java.awt.event.ActionEvent evt) {jMenuItem2ActionPerformed(evt);}});jMenu1.add(jMenuItem2);jMenuItem3.setText("\u4fdd\u5b58");jMenuItem3.addActionListener(new java.awt.event.ActionListener() {public void actionPerformed(java.awt.event.ActionEvent evt) {jMenuItem3ActionPerformed(evt);}});jMenu1.add(jMenuItem3);jMenuItem4.setText("\u53e6\u5b58\u4e3a");jMenuItem4.addActionListener(new java.awt.event.ActionListener() {public void actionPerformed(java.awt.event.ActionEvent evt) {jMenuItem4ActionPerformed(evt);}});jMenu1.add(jMenuItem4);jMenu1.add(jSeparator1);jMenu1.add(jSeparator2);jMenuItem6.setText("\u9000\u51fa");jMenuItem6.addActionListener(new java.awt.event.ActionListener() {public void actionPerformed(java.awt.event.ActionEvent evt) {jMenuItem6ActionPerformed(evt);}});jMenu1.add(jMenuItem6);jMenuBar1.add(jMenu1);jMenu2.setText("\u7f16\u8f91");jMenuItem7.setText("\u64a4\u9500");jMenu2.add(jMenuItem7);jMenuItem8.setText("\u526a\u5207");jMenu2.add(jMenuItem8);jMenuItem9.setText("\u590d\u5236");jMenu2.add(jMenuItem9);jMenuItem10.setText("\u7c98\u8d34");jMenu2.add(jMenuItem10);jMenuItem11.setText("\u5220\u9664");jMenu2.add(jMenuItem11);jMenuBar1.add(jMenu2);setJMenuBar(jMenuBar1);javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());getContentPane().setLayout(layout);layout.setHorizontalGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 400,Short.MAX_VALUE));layout.setVerticalGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 279,Short.MAX_VALUE));pack();}// </editor-fold>//GEN-END:initComponentsprivate void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:jTextArea1.setText(null);}private void jMenuItem4ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:FileDialog fd = new FileDialog(this, "另存新檔", FileDialog.SAVE);fd.setVisible(true);String string1 = jTextArea1.getText();String stringfile = fd.getDirectory()+fd.getFile();BufferedWriter bWriter = null;try {bWriter = new BufferedWriter(new FileWriter(stringfile));bWriter.write(string1); bWriter.close(); } catch (Exception e) {// TODO Auto-generated catch blockSystem.out.println("儲存失敗");} }private void jMenuItem3ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:String FileName = JOptionPane.showInputDialog("請輸入儲存的檔案名稱：");String string1 = jTextArea1.getText();if (FileName != null) {BufferedWriter bWriter = null;try {bWriter = new BufferedWriter(new FileWriter(new File(FileName)));bWriter.write(string1);bWriter.close();} catch (Exception e) {System.out.println("儲存失敗");}}}private void jMenuItem6ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:int result = JOptionPane.showConfirmDialog(null, "退出前是否儲存？");if (result == JOptionPane.YES_OPTION) {String FileName = JOptionPane.showInputDialog("請輸入儲存的檔案名稱：");String string1 = jTextArea1.getText();if (FileName != null) {BufferedWriter bWriter = null;try {bWriter = new BufferedWriter(new FileWriter(new File(FileName)));bWriter.write(string1);bWriter.close();} catch (Exception e) {System.out.println("儲存失敗");}}System.exit(0);} else if (result == JOptionPane.NO_OPTION) {System.exit(0);}}private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {// TODO add your handling code here:FileDialog fd = new FileDialog(this, "開啟", FileDialog.LOAD);fd.setVisible(true);String strFile = fd.getDirectory() + fd.getFile();if (strFile != null) {try {FileInputStream fis = new FileInputStream(strFile);byte[] buf = new byte[10 * 1024];int len = fis.read(buf);jTextArea1.append(new String(buf, 0, len));fis.close();} catch (Exception e) {System.out.println("開啟失敗");}}}public void SaveNotepad() {String FileName = JOptionPane.showInputDialog("請輸入儲存的檔案名稱：");String string1 = jTextArea1.getText();if (FileName != null) {BufferedWriter bWriter = null;try {bWriter = new BufferedWriter(new FileWriter(new File(FileName)));bWriter.write(string1);bWriter.close();//Thread.sleep(1000);} catch (Exception e) {e.printStackTrace();}}}/** * @param args the command line arguments */public static void main(String args[]) {java.awt.EventQueue.invokeLater(new Runnable() {public void run() {Test_Notepad notepad = new Test_Notepad("決Jue的記事本");notepad.setVisible(true);}});}//GEN-BEGIN:variables// Variables declaration - do not modifyprivate javax.swing.JMenu jMenu1;private javax.swing.JMenu jMenu2;private javax.swing.JMenuBar jMenuBar1;private javax.swing.JMenuItem jMenuItem1;private javax.swing.JMenuItem jMenuItem10;private javax.swing.JMenuItem jMenuItem11;private javax.swing.JMenuItem jMenuItem2;private javax.swing.JMenuItem jMenuItem3;private javax.swing.JMenuItem jMenuItem4;private javax.swing.JMenuItem jMenuItem6;private javax.swing.JMenuItem jMenuItem7;private javax.swing.JMenuItem jMenuItem8;private javax.swing.JMenuItem jMenuItem9;private javax.swing.JScrollPane jScrollPane1;private javax.swing.JSeparator jSeparator1;private javax.swing.JSeparator jSeparator2;private javax.swing.JTextArea jTextArea1;// End of variables declaration//GEN-END:variables}