Randomrandom=newRandom();if(fc>255)fc" />
JSP彩色验证码字母+数字.txt两个人吵架,先说对不起的人,并不是认输了,并不是原谅了。他只是比对方更珍惜这份感情。本文说明了如何在JSP中生成彩色的由数字加字母随机组成的验证码,以及不刷新页面改变验证码的方法.本文参考了网友的一些代码,并在此基础上做了一些修改!
产生验证码图片的文件image.jsp
<%@ page contentType="image/jpeg" import="java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*"
pageEncoding="UTF-8" %>
<%!Color getRandColor(int fc, int bc) {//给定范围获得随机颜色
Random random = new Random();
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc);
int g = fc + random.nextInt(bc - fc);
int b = fc + random.nextInt(bc - fc);
return new Color(r, g, b);
}%>
<%
//设置页面不缓存
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
// 在内存中创建图象
int width = 80, height = 20;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
//生成随机类
Random random = new Random();
// 设定背景色
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
//设定字体
g.setFont(new Font("Times New Roman", Font.BOLD, 18));
//画边框
g.setColor(new Color(0, 0, 0));
g.drawRect(0, 0, width - 1, height - 1);
// 随机产生155条干扰线,使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 155; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
// 取随机产生的认证码(4位数字)
String sRand = "";
for (int i = 0; i < 4; i++) {
String rand = null;
//随机生成数字或者字母
if (random.nextInt(10) > 5) {
rand = String.valueOf((char)(random
.nextInt(10) + 48));
} else {
rand = String.valueOf((char)(random
.nextInt(26) + 65));
}
sRand += rand;
// 将认证码显示到图象中
g.setColor(new Color(random.nextInt(80), random
.nextInt(80), random.nextInt(80)));
//调用函数出来的颜色相同,可能是因为种子太接近,所以只能直接生成 g.drawString(rand, 15 * i + 10, 16);
}
// 将认证码存入SESSION
session.setAttribute("rand", sRand);
// 图象生效
g.dispose();
// 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
%>
使用验证码图片的文件a.jsp
<%@ page contentType="text/html;charset=gb2312" %>
验证的页面check.jsp
<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<%
String rand = (String)session.getAttribute("rand");
String input = request.getParameter("rand");
%>
系统产生的认证码为: <%= rand %>
您输入的认证码为: <%= input %>
<%
if (rand.equals(input)) {
%>
输入相同,认证成功!
<%
} else {
%>
输入不同,认证失败!
<%
}
%>
本文来自CSDN博客,转载请标明出处:https://www.wendangku.net/doc/7917135084.html,/wlwqw/archive/2008/01/16/2046681.aspx
jsp验证码实现源代码 (2011-10-16 11:11:40) 验证码原理:①首先随机生成数字或字母;②把生成的数字或字母保存在Session这次会话中;③最后,在登陆页面上把接收用户输入的验证码与生成的验证码相匹配,成功返回TRUE,失败则返回FALSE; 演示程序包括三个文件: 1.login.jsp:登录页面 2.code.jsp:生成验证码图片页面 3.check.jsp:验证结果 code.jsp <%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*" %> <% // 在内存中创建图象 int width=60, height=20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); // 获取图形上下文 Graphics g = image.getGraphics(); // 设定背景色 g.setColor(new Color(0xDCDCDC)); g.fillRect(0, 0, width, height); //画边框 g.setColor(Color.black); g.drawRect(0,0,width-1,height-1); // 随机产生的认证码(4位数字) String rand =""+ (Math.random()*10000); rand = rand.substring(0,rand.indexOf(".")); switch(rand.length()) { case 1: rand = "000"+rand; break; case 2: rand = "00"+rand; break; case 3: rand = "0"+rand; break; default: rand = rand.substring(0,4); break; }
验证码识别常用算法 图像处理(验证码识别)程序中常用算法:灰度,二值化,去噪(1*1像素或者3*3像素等) 代码: view plaincopy to clipboardprint? //灰度 private void btnGray_Click(object sender, EventArgs e) { try { int Height = this.picBase.Image.Height; int Width = this.picBase.Image.Width; Bitmap newbitmap = new Bitmap(Width, Height); Bitmap oldbitmap = (Bitmap)this.picBase.Image; Color pixel; for (int x = 0; x < Width; x++) { for (int y = 0; y < Height; y++) { pixel = oldbitmap.GetPixel(x, y); newbitmap.SetPixel(x, y, Gray(pixel)); } } this.picBase.Image = newbitmap; } catch (Exception err) { MessageBox.Show("灰度化失败原因:" + err.Message); } } //灰度化算法 protected static Color Gray(Color c) { int rgb = Convert.ToInt32((double)(((0.3 * c.R) + (0.59 * c.G)) + (0.11 * c.B))); return Color.FromArgb(rgb, rgb, rgb); } //灰度 private void btnGray_Click(object sender, EventArgs e) { try { int Height = this.picBase.Image.Height; int Width = this.picBase.Image.Width; Bitmap newbitmap = new Bitmap(Width, Height); Bitmap oldbitmap = (Bitmap)this.picBase.Image; Color pixel; for (int x = 0; x < Width; x++) { for (int y = 0; y < Height; y++) { pixel = oldbitmap.GetPixel(x, y);
关于jsp验证码生成,显示,验证和刷新: 1:四位数据的验证图片生成,用servlet实现 2:在web.xmlli配置servlet 3:页面上显示servlet生成的图片 4:关于验证码输入数据的验证 5:验证码的刷新 ——————————————————————– 1:四位数据的验证图片生成,用servlet实现,servlet代码如下: import java.io.*; import javax.servlet.http.*; import javax.servlet.*; import java.util.*; import java.awt.*; import java.awt.image.*; import javax.imageio.*; public class vImage extends HttpServlet { public void init(ServletConfig conf) throws ServletException { super.init(conf); } public void doGet(HttpServletR equest req, HttpServletResponse res) throws ServletException, IOException { res.setContentType(‖image/jpeg‖); res.setHeader(‖Pragma‖, ―No-cache‖); res.setHeader(‖Cache-Control‖, ―no-cache‖); res.setDateHeader(‖Expires‖, 0); HttpSession session = req.getSession(); // 在内存中创建图象 int width = 60, height = 20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); // 获取图形上下文 Graphics g = image.getGraphics(); // 生成随机类 Random random = new Random();
[原]自动生成验证码图片的工具类,收藏起来备用。用法:直接调用其静态方法即可。 Map
jsp页面验证码源代码 在java后台中生成验证码的ImageIO传到前端页面显示,同时把验证码的v alue值传入session 中用于与用户输入的验证码进行匹配,在用户验证中使用ajax技术,在不刷新页面的同时进行验证码验证。 程序结构图: VerifyCodeUtils程序主要内容为通过Java生成验证码的图片,以及验证码的value值,程序如下: package utils; import java.awt.Color; import java.awt.Font;
import java.awt.Graphics2D; import java.awt.image.BufferedImage; import java.util.HashMap; import java.util.Map; import java.util.Random; publicclass VerifyCodeUtils { privatestatic BufferedImage image = null; privatestatic Random random = new Random(); //在自己定义的一些数中,生成4位随机数 publicstatic String getVerifyCode() { String str = ""; char[] code = newchar[]{'A','B','C','D','E','F','G','H','I ','J','K','L','M','N','P','Q','R','S','T','U', 'V','W','X','Y','Z','a','b','c','d','e','f','g','h','i',' j','k','m','n','p','q','r','s','t', 'u','v','w','x','y','z','2','3','4','5','6','7','8','9'}; Random random = new Random(); for(int i = 0; i <4; i++) { str += String.valueOf(code[random.nextInt(code.length)]); } return str; }
Function body(a,b,c) dim aa aa=a aa=mid(aa,instr(aa,b) len(b)) body=left(aa,instr(aa,c)-1) End Function Public Function StringToBytes(ByVal strData, ByVal strCharset) Dim objFile Set objFile = CreateObject("ADODB.Stream") objFile.Type = adTypeText objFile.Charset = strCharset objFile.Open objFile.WriteText strData objFile.Position = 0 objFile.Type = adTypeBinary If UCase(strCharset) = "UNICODE" Then objFile.Position = 2 'delete UNICODE BOM ElseIf UCase(strCharset) = "UTF-8" Then objFile.Position = 3 'delete UTF-8 BOM End If StringToBytes = objFile.Read(-1) objFile.Close Set objFile = Nothing End Function Private Function GetFileBinary(ByVal strPath) Dim objFile Set objFile = CreateObject("ADODB.Stream") objFile.Type = adTypeBinary objFile.Open objFile.LoadFromFile strPath GetFileBinary = objFile.Read(-1) objFile.Close Set objFile = Nothing End Function
//登入页面 $conn=mysql_connect('127.0.0.1','root','')or die("连接失败"); mysql_select_db('tujian',$conn)or die("未找到该数据库"); define(ALL_PS,"vivid");mysql_query("set names GBK"); if($_POST[submit]){ $postcode=strtolower($_POST["code"]); $postcode=strtoupper($_POST["code"]); $uid=str_replace(" ","",$_POST[uid]); $sql="select * from users where `uid`='$_POST[uid]'"; $query=mysql_query($sql); $user=is_array($row=mysql_fetch_array($query)); $mi=$user?md5($_POST[pass].ALL_PS)==$row[pass]:FALSE; if($mi){ $_SESSION[uid]=$row[uid]; $_SESSION[name]=$row[name]; $_SESSION[id]=$row[id]; $_SESSION[user_shell]=md5($row[uid].$row[pass].ALL_PS); if( $_SESSION["code"]==$postcode){ echo""; }else{ echo"