文件的打开保存另存为功能代码实现-蒲公英云

文件的打开保存另存为功能代码实现

Center （效果图）

import java.awt.BorderLayout;
public class NotePad
{
private JFrame jf;

private JMenuBar menu;  
private JMenuItem open;

public class NotePad
{
private JFrame jf;

private JMenuBar menu;  
private JMenuItem open;  
private JMenuItem save;  
private JMenuItem saveAs;  
private JMenu file;  
private JMenu help;  
private JMenuItem about;  
private JTextArea textArea;  
private String filePath;  
public void show()   
\{  
    init();  
    setStyle();  
    registHandler();  
    jf.setDefaultCloseOperation(JFrame.EXIT\_ON\_CLOSE);  
    jf.setVisible(true);  
\}  
//表单控件初始化  
private void init()  
\{  
    jf = new JFrame();  
    menu = new JMenuBar();   
    open = new JMenuItem("打开");  
    save = new JMenuItem("保存");  
    saveAs = new JMenuItem("另存为");  
    file = new JMenu("文件");  
    help = new JMenu("帮助");  
    about = new JMenuItem("关于");  
    textArea = new JTextArea();  
\}  
//表单控件的添加  
private void setStyle()  
\{  
    jf.setSize(600, 600);  
    menu.add(file);   
    menu.add(help);  
    file.add(open);  
    file.add(save);   
    file.add(saveAs);  
    help.add(about);  
    jf.add(menu, BorderLayout.NORTH);  
    JScrollPane jsp = new JScrollPane(textArea);  
    jf.add(jsp);  
\}

交互事件

private void registHandler()  
\{   //给打开按钮添加事件监听（方法实现）  
    open.addActionListener(new ActionListener()  
    \{  
        @Override  
        public void actionPerformed(ActionEvent e)  
        \{  
            FileDialog fd = new FileDialog(jf);  
            fd.setVisible(true);  
            if (fd.getFile() != null)  
            \{  
                filePath = fd.getDirectory() + fd.getFile();  
                BufferedReader br = null;  
                try  
                \{  
                    br = new BufferedReader(new InputStreamReader(new FileInputStream(filePath)));  
                    String line = null;  
                    while ((line = br.readLine()) != null)  
                    \{  
                        textArea.append(line + "\\n");  
                    \}  
                \}  
                catch (Exception e2)  
                \{  
                    e2.printStackTrace();  
                \}  
                finally  
                \{  
                    if (br != null)  
                    \{  
                        try  
                        \{  
                            br.close();  
                        \}  
                        catch (IOException e1)  
                        \{  
                            e1.printStackTrace();  
                        \}  
                    \}  
                \}  
            \}  
        \}  
    \});  
    //给保存按钮添加事件监听（方法实现）  
    save.addActionListener(new ActionListener()  
    \{  
        @Override  
        public void actionPerformed(ActionEvent e)  
        \{  
            // 如果filePath为null  
            save(false);  
        \}  
    \});  
      //给另存为按钮添加事件监听（方法实现）  
    saveAs.addActionListener(new ActionListener()  
    \{  
        @Override  
        public void actionPerformed(ActionEvent e)  
        \{  
            save(true);  
        \}  
    \});  
\}  
private void save(boolean isSaveAs)  
\{  
    while(filePath == null || isSaveAs)  
    \{  
        FileDialog fd = new FileDialog(jf);  
        fd.setVisible(true);  
        if(fd.getFile()==null)  
        \{  
            continue;  
        \}  
        filePath = fd.getDirectory() + fd.getFile();  
    \}  
    PrintWriter pw = null;  
    try  
    \{  
        pw = new PrintWriter(filePath);  
        pw.println(textArea.getText());  
    \}  
    catch (Exception e)  
    \{  
        e.printStackTrace();  
    \}finally\{  
        if(pw != null)  
        \{  
            pw.close();  
        \}  
    \}  
\}  
//主函数调用菜单界面  
public static void main(String\[\] args)  
\{  
    new NotePad().show();  
\}