随机生成验证码

自动生成30道小学四则运算验证码

1.     设计思想

利用JFrame从而实现，编写两个类，第二个用来实现验证码的相关操作

2.     源程序代码

//班级：信1705-2

//姓名：马旺旺

//学号：20173564

import java.awt.*;

 

import javax.swing.*;

 

public class Yanzheng extends JFrame {

     

      private JLabel userLa;

    private JLabel pwdLa;

    private JLabel verCodeLa;//验证码

    private JTextField userTxt;

    private JPasswordField pwdTxt;

    private JTextField verCodeTxt;//验证码

    private JButton sureBt;

    private JButton quitBt;

    private Yangzhengma mp;

 

    //构造方法

    public Yanzheng()

    {

        Init();

    }

    public void Init()

    {

        this.setTitle("请登入");

 

        //创建出控件对象（因为上面只是声明出来，并没有给出实际的空间)

 

        //用户文本

        userLa = new JLabel();

        userLa.setText("用户名：");

        userLa.setSize(60, 50);

        userLa.setLocation(100, 80);

 

        //密码文本

        pwdLa = new JLabel();

        pwdLa.setText("密码：");

        pwdLa.setSize(50, 50);

        pwdLa.setLocation(100, 120);

 

        //用户输入框

        userTxt = new JTextField();

        userTxt.setSize(100, 30);

        //this.setSize(width, height)

        userTxt.setLocation(170, 95);

 

        //密码输入框

        pwdTxt = new JPasswordField();

        pwdTxt.setSize(100, 30);

        pwdTxt.setLocation(170, 135);

 

        //登陆

        sureBt = new JButton("登录");

        sureBt.setSize(100, 25);

        sureBt.setLocation(135, 220);

 

        //快速注册

        quitBt = new JButton("快速注册");

        quitBt.setSize(100, 25);

        quitBt.setLocation(135,260);

 

        //验证码文本

        verCodeLa = new JLabel();

        verCodeLa.setText("验证码：");

        verCodeLa.setSize(60, 50);

        verCodeLa.setLocation(100,165);

 

        //验证码文本框

        verCodeTxt = new JTextField();

        verCodeTxt.setSize(100, 30);

        verCodeTxt.setLocation(170, 180);

 

        //验证码

        mp = new Yangzhengma();

        mp.setSize(100, 30);

        mp.setLocation(280, 175);

 

        this.setLayout(null);

        this.setSize(500, 400);

        this.add(userLa);

        this.add(pwdLa);

        this.add(userTxt);

        this.add(pwdTxt);

        this.add(sureBt);

        this.add(quitBt);

        this.add(verCodeLa);

        this.add(verCodeTxt);

        this.add(mp);

        this.setVisible(true);

    }

 

public static void main(String[] args) {

      new Yanzheng();

}

 

}

package 练习一;

 

import java.awt.*;

import java.util.*;

public class Yangzhengma extends Panel {

    public void paint(Graphics g)

    {

        int height = 50;

        int width = 90;

        //验证码框背景颜色

        g.setColor(Color.BLUE);

        //填充验证码背景

        g.fillRect(0, 0, width, height);

        g.setColor(Color.BLACK);

        g.drawRect(0, 0, width-1, height-1);

        Random r = new Random();

        //设置干扰点

        for(int i = 0;i<100;i++)

        {

            int x = r.nextInt(width)-1;

            int y = r.nextInt(height)-1;

            g.drawOval(x, y, 2, 2);

        }

        g.setFont(new Font("黑体",Font.BOLD,20));//设置验证码字体以及大小

        g.setColor(Color.red);//设置验证码字体颜色

        //生成随机验证码

        char[] tmp = ("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();

        StringBuilder sb = new StringBuilder();

        for(int i = 0;i<4;i++)

        {

            int pos = r.nextInt(tmp.length);

            char c = tmp[pos];

            sb.append(c + " ");

        }

        g.drawString(sb.toString(), 10, 15);//写入验证码

    }

}

3.     实现结果截图

   

4.     实验总结

     本次实验为做一个文本框软件，验证码的实质即为随机数的综合应用，添加了英文字母的应用。