帮忙看看什么问题？？
package cn.com.checkCode;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
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 {
private static final long serialVersionUID = 1L;
public static final int WIDTH=120;
public static final int HEIGHT=25;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
BufferedImage image=new BufferedImage(WIDTH,HEIGHT,BufferedImage.TYPE_INT_RGB);
Graphics g=image.getGraphics();
//设置背景色
setBackGround(g);
//设置边框
setBorder(g);
//画干扰线
drawRandomLine(g);
//写随机数
String num=drawRandomNum((Graphics2D)g);
System.out.println(num);
request.getSession().setAttribute("imageCheckCode", num);
response.setContentType("image/jpeg");
response.setDateHeader("expries", -1);
response.setHeader("Cache-Control", "no-control");
response.setHeader("prama", "no-control");
ImageIO.write(image, "jpg", response.getOutputStream());
}
private String drawRandomNum(Graphics2D g) {
g.setColor(Color.PINK);
g.setFont(new Font("宋体",Font.BOLD,20));
int x=10;
StringBuffer sb=new StringBuffer();
for(int i=0;i<4;i++)
{
int degree=new Random().nextInt()%30;
int num=new Random().nextInt(9);
String str=num+"";
sb.append(str);
g.rotate(degree*Math.PI/180, x, 20);
g.drawString(str, x, 20);
g.rotate(-degree*Math.PI/180, x, 20);
x+=30;
}
return sb.toString();
}
private void drawRandomLine(Graphics g) {
g.setColor(Color.blue);
for(int i=0;i<5;i++)
{
int x1=new Random().nextInt(WIDTH-4)+2;
int y1=new Random().nextInt(HEIGHT-4)+2;
int x2=new Random().nextInt(WIDTH-2);
int y2=new Random().nextInt(HEIGHT-2);
g.drawLine(x1, y1, x2, y2);
}
}
private void setBorder(Graphics g) {
g.setColor(Color.GREEN);
g.drawRect(1, 1, WIDTH-2, HEIGHT-2);
}
private void setBackGround(Graphics g) {
g.setColor(Color.gray);
g.fillRect(0, 0, WIDTH, HEIGHT);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
}
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>MyHtml.html</title>
<script type="text/javascript">
function changeImag(image)
{
image.src=image.src+"?"+new Date().getTime();
}
</script>
</head>
<body>
<form action="/Session/RegisterServlet" >
用户名：<input type="text" name="userName"/>
<br/>
密码：<input type="password" name="password"/>
<br/>
人证码：<input type="text" name="numRandom">
<img src="/Session/ImageServlet" onclick="changeImag(this)" style="cursor:hand">
<br/>
<input type="submit" value="提交"/>
<input type="reset" value="重置"/>
</form>
</body>
</html>
package cn.com.checkCode;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class RegisterServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("UTF-8");
PrintWriter out=response.getWriter();
//处理请求之前校验验证码是否正确
String random=request.getParameter("numRandom");
String s_check=(String)request.getAttribute("imageCheckCode");
System.out.println(s_check);
System.out.println(random);
if(s_check!=null&&random!=null&& random.equals(s_check))
{
out.print("注册成功！");
System.out.println("注册成功");
}
else
{
out.print("注册失败！");
System.out.println("注册失败！");
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
}
可是那个图片上的绘制的随机数传不过去，最下面的那个Servlet里面输出的s_check的值为null
你早说不就好了
设置 request.getSession().setAttribute("imageCheckCode", num);
获取 request.getAttribute("imageCheckCode");
你看2个一致吗
