前台html代码
[Java] 纯文本查看 复制代码 <div style="margin-top: 50px;">
<span>验证码：</span><input type="text" name="verifyCode" id="verifyCode" style="width: 75px;height: 25px;"/>
<img id="verifyCodeImg" alt="点击更换" src="/qos/dog/getVerifyCodeImg"
title="点击更换">
</div>
注释：此处的src="/qos/dog/getVerifyCodeImg" SpringBoot页面展示Thymeleaf的语法
前台js代码
[Java] 纯文本查看 复制代码 function change() {
var verifyCode = document.getElementById("verifyCodeImg");
verifyCode.src = "/qos/dog/getVerifyCodeImg?time=" + Math.random(1000);
}
/*-*/
/qos/dog/ 这里的路径是需要换成自己的哦
验证代码，在controller里面新建一个util文件夹，然后放入VerifyCodeUtil.java 代码如下 [Java] 纯文本查看 复制代码 package com.paladin.qos.util;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Random;
public class VerifyCodeUtil {
private static final Random random = new Random();
private static final String[] fontNames = {"宋体", "华文楷体", "黑体", "Georgia", "微软雅黑", "楷体_GB2312"};
public static String drawImage(ByteArrayOutputStream output) {
String code = "";
int width = 50;
int height = 25;
//创建图片缓冲区
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);
Graphics2D g = bi.createGraphics();
//设置背景颜色
g.setBackground(new Color(255, 255, 255));
g.clearRect(0, 0, width, height);
StringBuilder stringBuilder = new StringBuilder();
//这里只画入四个字符
for (int i = 0; i < 4; i++) {
String s = randomChar() + ""; //随机生成字符，因为只有画字符串的方法，没有画字符的方法，所以需要将字符变成字符串再画
stringBuilder.append(s); //添加到StringBuilder里面
float x = i * 1.0F * width / 4; //定义字符的x坐标
g.setFont(randomFont()); //设置字体，随机
g.setColor(randomColor()); //设置颜色，随机
g.drawString(s, x, height - 5);
}
code = stringBuilder.toString();//获取验证码字符串
//定义干扰线
//定义干扰线的数量（3-5条）int num = random.nextInt(max)%(max-min+1) + min;
int num = random.nextInt(5) % 3 + 3;
Graphics2D graphics = (Graphics2D) bi.getGraphics();
for (int i = 0; i < num; i++) {
int x1 = random.nextInt(width);
int y1 = random.nextInt(height);
int x2 = random.nextInt(width);
int y2 = random.nextInt(height);
graphics.setColor(randomColor());
graphics.drawLine(x1, y1, x2, y2);
}
// 释放图形上下文
g.dispose();
try {
ImageIO.write(bi, "jpg", output);
} catch (IOException e) {
e.printStackTrace();
}
return code;//为了方便取值，直接返回code，
}
//随机字体
private static Font randomFont() {
int index = random.nextInt(fontNames.length);
String fontName = fontNames[index];
int style = random.nextInt(4); //随机获取4种字体的样式
int size = random.nextInt(20) % 6 + 15; //随机获取字体的大小(10-20之间的值)
return new Font(fontName, style, size);
}
//随机颜色
private static Color randomColor() {
int r = random.nextInt(225);
int g = random.nextInt(225);
int b = random.nextInt(225);
return new Color(r, g, b);
}
//随机字符
private static char randomChar() {
//A-Z,a-z,0-9,可剔除一些难辨认的字母与数字
String str = "0123456789ABCdefghiDEFGHIJopPQRVWXYZabcjklSTUmnqrstKLMNOvuwxyz";
return str.charAt(random.nextInt(str.length()));
}
}
最后，在controller里面引用 [Java] 纯文本查看 复制代码 @RequestMapping("/getVerifyCodeImg")
@ResponseBody
public void getVerifyCodeImg(HttpServletResponse response, HttpSession session) {
ByteArrayOutputStream output = new ByteArrayOutputStream();
String code = VerifyCodeUtil.drawImage(output);
//将验证码文本直接存放到session中
session.setAttribute("verifyCode", code);
try {
ServletOutputStream out = response.getOutputStream();
output.writeTo(out);
} catch (IOException e) {
e.printStackTrace();
}
}
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