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验证码不显示

来源：2-2 验证码的代码实现

qq_柒分醉_03927370

2016-10-13 21:06

<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'index.jsp' starting page</title>

<!--

-->

</head>

<body>

验证码：<input type="text" name = "checkcode"/>

<img alt="验证码" src="<%= request.getContextPath();%>/servlet/ImageServlet"/>

<<a href="javascript:reloadCode();">看不清楚</a><br>

</body>

</html>

package com.Servlet;

import java.awt.Color;

import java.awt.Graphics;

import java.awt.image.BufferedImage;

import java.io.IOException;

import java.util.Random;

import javax.imageio.ImageIO;

import javax.imageio.spi.ImageWriterSpi;

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){

BufferedImage bi = new BufferedImage(68, 26,BufferedImage.TYPE_INT_RGB);

Graphics g = bi.getGraphics();

Color c = new Color(200, 150, 255);

g.setColor(c);

g.fillRect(0, 0, 68, 26);

char[] ch = "ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789".toCharArray();

Random r = new Random();

int len = ch.length,index;

StringBuffer sb = new StringBuffer();

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.drawString(ch[index]+" ", (i*15)+3,18 );

sb.append(ch[index]);

}

request.getSession().setAttribute("piccode",sb.toString() );

try {

ImageIO.write(bi, "JPG", response.getOutputStream());

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

写回答关注

5回答

qq_小二_9

2016-10-18 09:22:09

选择创建Servlet类，不要自己手敲，他会自动生成web配置把那个访问servlet的路径直接复制在JSP页面上

2 0

qq_梦想在... 回复weibo爱...

把你做的这个项目直接删除，重新做。在建ImageServlet class文件时，直接建一个servlet文件，把ImageServlet的程序直接复制过去就好了，servlet文件会自动生成xml都不需要配置，就可以直接运行了。

2016-11-27 12:39:25

共 2 条回复 >
_犊子哥哥_

2016-10-15 18:28:33

貌似是imagecodeservlet那个servlet根本没有执行，我也遇到一样的问题了，还没有解决，楼主有解了不?

1 0

浮生半夏1

解决了吗？

2018-01-17 23:22:07

共 1 条回复 >
qq_柒分醉_03927370

2016-10-14 14:49:00

web.xml里的字母大小写问题。找出来原因了

0 0
七夕海堂

2016-10-14 14:29:43

图片地址中的 src="<%= request.getContextPath();%>/servlet/ImageServlet"去掉里面的分号再试试

0 0
han911223

2016-10-14 14:26:25

你的Web.xml文件配置了吗？贴出来看看

0 0