验证码

JS简单验证码： var code; function createCode() { code = ""; var codeLength = 4; var checkCode = document.getElementById("checkCode"); var selectChar = new Array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "g", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"); for (var i = 0; i < codeLength; i=i+1) { var charIndex = Math.floor(Math.random() * 62); code += selectChar[charIndex]; } if (checkCode) { checkCode.value = code; } } JSP验证码： <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@page import="java.awt.image.BufferedImage"%> <%@page import="java.awt.Graphics2D"%> <%@page import="java.awt.Color"%> <%@page import="java.awt.Font"%> <%@page import="javax.imageio.ImageIO"%> <% int width = 60; int height = 20; // 创建具有可访问图像数据缓冲区的Image BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D g = buffImg.createGraphics(); // 创建一个随机数生成器 Random random = new Random(); g.setColor(Color.WHITE); g.fillRect(0, 0, width, height); // 创建字体，字体的大小应该根据图片的高度来定 Font font = new Font("Times New Roman", Font.PLAIN, 18); // 设置字体 g.setFont(font); // 画边框 g.setColor(Color.BLACK); g.drawRect(0, 0, width - 1, height - 1); // 随机产生160条干扰线 g.setColor(Color.LIGHT_GRAY); for (int i = 0; i < 160; i++) { int x = random.nextInt(width); int y = random.nextInt(height); int x1 = random.nextInt(12); int y1 = random.nextInt(12); g.drawLine(x, y, x + x1, y + y1); } // randomCode 用于保存随机产生的验证码 StringBuffer randomCode = new StringBuffer(); int red = 0, green = 0, blue = 0; // 随机产生4位数字的验证码 for (int i = 0; i < 4; i++) { // 得到随机产生的验证码数字 String strRand = String.valueOf(random.nextInt(10)); // 产生随机的颜色分量来构造颜色值 red = random.nextInt(110); green = random.nextInt(50); blue = random.nextInt(50); // 用随机产生的颜色将验证码绘制到图像中 g.setColor(new Color(red, green, blue)); g.drawString(strRand, 13 * i + 6, 16); randomCode.append(strRand); } // 将四位数字的验证码保存到session中 //HttpSession session = request.getSession(); session.setAttribute("randomCode", randomCode.toString()); // 禁止图像缓存 response.setHeader("Pragma", "no-cache"); response.setHeader("Cache-Control", "no-cache"); response.setDateHeader("Expires", 0); response.setContentType("image/jpeg"); // 将图像输出到servlet输出流中 ServletOutputStream sos = response.getOutputStream(); ImageIO.write(buffImg, "jpeg", sos); sos.close(); //sos = null; out.clear(); out = pageContext.pushBody(); %>