验证码登陆问题？ 本帖最后由 yabbi215 于 2009-08-21 13:45:00 编辑 解决方案 » 免费领取超大流量手机卡，每月29元包185G流量+100分钟通话, 中国电信官方发货 在JSP中,只要简单实现就可以了。谢谢了！！！ ImageServlet.javapackage com.mobile.control;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.IOException;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class ImageServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } // 生成数字和字母的验证码 public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { BufferedImage img = new BufferedImage(68, 22, BufferedImage.TYPE_INT_RGB); // 得到该图片的绘图对象 Graphics g = img.getGraphics(); Random r = new Random(); Color c = new Color(200, 150, 255); g.setColor(c); // 填充整个图片的颜色 g.fillRect(0, 0, 68, 22); // 向图片中输出数字和字母 StringBuffer sb = new StringBuffer(); char[] ch = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray(); int index, len = ch.length; for (int i = 0; i < 4; i ++) { index = r.nextInt(len); g.setColor(new Color(r.nextInt(88), r.nextInt(188), r.nextInt(255))); g.setFont(new Font("Arial", Font.BOLD | Font.ITALIC, 22));// 输出的字体和大小 g.drawString("" + ch[index], (i * 15) + 3, 18);//写什么数字，在图片的什么位置画 sb.append(ch[index]); } request.getSession().setAttribute("piccode", sb.toString()); ImageIO.write(img, "JPG", response.getOutputStream()); } }web.xml<servlet> <servlet-name>ImageServlet</servlet-name> <servlet-class>com.mobile.control.ImageServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ImageServlet</servlet-name> <url-pattern>/servlet/ImageServlet</url-pattern> </servlet-mapping>页面<html><head><title>验证码</title><script type="text/javascript">function changeImage(){document.getElementById("safeCode").src="servlet/ImageServlet?date="+new Date().getTime();}</script></head><body><img id="safeCode" src="servlet/ImageServlet"/><a href="#" onclick="changeImage()">看不清楚</a></body></html> HTML5 video全屏问题 求教一个简单的新手问题 如何捕获鼠标在iframe里？ JS调用问题 求助:javascript语法问题 字符串前后倒 关闭页面时就不能打开新窗口了吗？ setInterval()有Bug? 如何让页面刷新之后不记住上次的checkbox选择？ 当鼠标移到某文字上，出现一个浮动层，描述该文字的含义。怎样做。以前见过，可现在找不到 ext异步加载json的问题,又写了一个combo还是加载不了,烦,初学,请求支援 textarea 与 execCommand
package com.mobile.control;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.IOException;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class ImageServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } // 生成数字和字母的验证码 public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { BufferedImage img = new BufferedImage(68, 22, BufferedImage.TYPE_INT_RGB); // 得到该图片的绘图对象 Graphics g = img.getGraphics(); Random r = new Random(); Color c = new Color(200, 150, 255); g.setColor(c); // 填充整个图片的颜色 g.fillRect(0, 0, 68, 22); // 向图片中输出数字和字母 StringBuffer sb = new StringBuffer(); char[] ch = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray(); int index, len = ch.length; for (int i = 0; i < 4; i ++) { index = r.nextInt(len); g.setColor(new Color(r.nextInt(88), r.nextInt(188), r.nextInt(255))); g.setFont(new Font("Arial", Font.BOLD | Font.ITALIC, 22));// 输出的字体和大小 g.drawString("" + ch[index], (i * 15) + 3, 18);//写什么数字，在图片的什么位置画 sb.append(ch[index]); } request.getSession().setAttribute("piccode", sb.toString()); ImageIO.write(img, "JPG", response.getOutputStream()); } }web.xml
<servlet> <servlet-name>ImageServlet</servlet-name> <servlet-class>com.mobile.control.ImageServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ImageServlet</servlet-name> <url-pattern>/servlet/ImageServlet</url-pattern> </servlet-mapping>页面<html>
<head>
<title>验证码</title>
<script type="text/javascript">
function changeImage()
{
document.getElementById("safeCode").src="servlet/ImageServlet?date="+new Date().getTime();
}
</script>
</head>
<body>
<img id="safeCode" src="servlet/ImageServlet"/><a href="#" onclick="changeImage()">看不清楚</a>
</body>
</html>