java记事本可以打开文件保存文件和退出的程序

Dear 丶 2022-05-17 07:19 215阅读 0赞

import java.awt.*;
    import java .awt.event.*;
    import java.io.*;
    class win 
    {
    	Frame a;
    	MenuBar menubar;
    	Menu menu1;
    	File file;
    	MenuItem item1,item2,item3;	
    	FileDialog opendia,savedia;
    	TextArea t;
    	win()
    	{
    		a=new Frame("日记本");
    		Init();
    	}
    	public void Init()
    		{
    			
    			menubar=new MenuBar();
    			menu1=new Menu("文件");
    			item1=new MenuItem("打开");
    			item2=new MenuItem("保存");
    			item3=new MenuItem("退出");
    			menu1.add(item1);
    			menu1.add(item2);
    			menu1.add(item3);
    			menubar.add(menu1);
    			a.setMenuBar(menubar);
    			
    			t=new TextArea();
    			a.add(t);
    			opendia=new FileDialog(a,"打开",FileDialog.LOAD);
    			savedia=new FileDialog(a,"保存",FileDialog.SAVE);
    			a.setBounds(150,150,640,480);
    			a.setVisible(true);
    			myevent();
    			
    			
    		}
    		public void myevent()
    		{
    			a.addWindowListener(new WindowAdapter()
    				{
    				public void windowClosing(WindowEvent e)
    				{
    					System.exit(0);
    				}
    				});
    				item3.addActionListener(new ActionListener()
    				{
    					public void actionPerformed(ActionEvent e)
    					{
    						System.exit(0);
    					}
    				});
    				item1.addActionListener(new ActionListener()
    				{
    					public void actionPerformed(ActionEvent e)
    					{
    						opendia.setVisible(true);
    						String dirPath=opendia.getDirectory();
    						String fileName=opendia.getFile();
    						if(dirPath==null||fileName==null)
    						return ;
    						t.setText("");
    						file=new File(dirPath,fileName);
    						try
    						{BufferedReader bfrd=new BufferedReader(new FileReader(file));
    						String line=null;
    						while((line=bfrd.readLine())!=null)
    							{t.append(line+"\r\n");
    							}bfrd.close();
    						}
    						catch(IOException ex)
    						{throw new RuntimeException("读取失败");
    							}	
    					} 
    				});
    				item2.addActionListener(new ActionListener()
    				{
    					public void actionPerformed(ActionEvent e)
    					{
    							if(file==null)
    						{	
    						savedia.setVisible(true);
    						String dirPath=savedia.getDirectory();
    						String fileName=savedia.getFile();
    						if(dirPath==null||fileName==null)
    						return ;
    						file=new File(dirPath,fileName);
    						}
    						try
    							{
    								BufferedWriter bfwt=new BufferedWriter(new FileWriter(file));
    								String text= t.getText();
    								bfwt.write(text);
    								bfwt.close();
    								t.setText("");
    							}
    						catch(IOException ex)
    							{
    								throw new RuntimeException();
    							}
    					}
    				});
    				}
    				
    }
    class window1 {
    	
    
    	public static void main(String[] args) 
    	{
    	 win a=new win();
    	}	
    }

![1352123039_6145.jpg][]

[1352123039_6145.jpg]: https://img-my.csdn.net/uploads/201211/05/1352123039_6145.jpg