java第一次上机实验--验证码

 1 package javashiyan; 2  3 import java.awt.Color; 4 import java.awt.event.ActionEvent; 5 import java.awt.event.ActionListener; 6  7 import javax.swing.*; 8  9 public  class Yanzhen extends JFrame10 {11     //定义成员变量12     private Mypanel mp;13     private JButton b;14     private JTextField txt;15     private ActionListener listener;16     17     public Yanzhen()18     {19         Realize();20     }21     public void Realize()22     {23         JFrame f=new JFrame("验证码");24         //实例化25         b=new JButton();26         b.addActionListener(listener);27         ActionEvent e;28         b.setIcon(new ImageIcon("D://button//刷新.jpg"));//载入图片29         b.setLocation(200,100);//设置位置30         b.setSize(32,32);//设置大小31         b.setVisible(true);//设置显示32         33         txt=new JTextField();34         txt.setSize(90,30);35         txt.setLocation(10,100);36         txt.setVisible(true);37         38         mp=new Mypanel();39         mp.setSize(100,30);40         mp.setLocation(100,100);41         42         JButton jb=new JButton();43         44         45         f.add(mp);46         f.add(b);47         f.add(txt);48         49         f.setLayout(null);50         f.setSize(400, 400);//设置界面大小51         f.getContentPane().setBackground(Color.white);//设置界面的背景颜色52         f.getContentPane().setVisible(true);53         f.setVisible(true);54     }55 56 57 58     public void actionPerformed(ActionEvent e) {59         // TODO Auto-generated method stub60         61         62     }63 }

 1 package javashiyan; 2  3 import java.awt.*; 4 import java.util.*; 5  6 public class Mypanel extends Panel { 7     public void paint(Graphics g) 8     { 9         int height = 50;10         int width = 90;11         //验证码框背景颜色12         g.setColor(Color.white);13         //填充验证码背景14         g.fillRect(0, 0, width, height);15         g.setColor(Color.BLACK);16         g.drawRect(0, 0, width-1, height-1);17         Random r = new Random();18         for(int i = 0;i<100;i  )19         {20             int x = r.nextInt(width)-1;21             int y = r.nextInt(height)-1;22             g.drawOval(x, y, 2, 2);//画干扰的圆点23         }24         for(int i=0;i<3;i  )25         {26             int x1=r.nextInt(width)-1;27             int y1=r.nextInt(height)-1;28             int x2=r.nextInt(width)-1;29             int y2=r.nextInt(height)-1;30             g.drawLine(x1, y1, x2, y2);//画干扰的线段31         }32         33         g.setFont(new Font("黑体",Font.BOLD,20));//设置验证码字体以及大小34         g.setColor(Color.BLUE);//设置验证码字体颜色35         //生成随机验证码36         char[] tmp = ("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();37         StringBuilder sb = new StringBuilder();38         for(int i = 0;i<4;i  )39         {40             int pos = r.nextInt(tmp.length);41             char c = tmp[pos];42             sb.append(c   " ");43         }44         g.drawString(sb.toString(), 10, 15);//写入验证码45     }46 }

 1 package javashiyan; 2  3  4  5 import java.util.Random; 6  7 public class main { 8  9     public static void main(String[] args) 10     {    11             Yanzhen dang=new Yanzhen();12     }13 14 }15         

 

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