<%@ 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); // 取随机产生的认证码(4位数字) String rand = request.getParameter("rand"); 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; } // 将认证码存入SESSION session.setAttribute("rand",rand); // 将认证码显示到图象中 g.se tColor(Color.black); Integer tempNumber = new Integer(rand); String numberStr = tempNumber.toString(); g.setFont(new Font("Atlantic Inline",Font.PLAIN,18)); String Str = numberStr.substring(0,1); g.drawString(Str,8,17); Str = numberStr.substring(1,2); g.drawString(Str,20,15); Str = numberStr.substring(2,3); g.drawString(Str,35,18); Str = numberStr.substring(3,4); g.drawString(Str,45,15); // 随机产生88个干扰点,使图象中的认证码不易被其它程序探测到 Random random = new Random(); for (int i=0;i<20;i++) { int x = random.nextInt(width); int y = random.nextInt(height); g.drawOval(x,y,0,0); } // 图象生效 g.dispose(); // 输出图象到页面 ImageIO.write(image, "JPEG", response.getOutputStream()); %>
come in the learning~~~~~~进来学习下哈 o(∩_∩)o...
//这是image.jsp,用来生成验证码<%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*" pageEncoding="gbk"%> <%! 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=60, height=20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// 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); }
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); // 取随机产生的认证码(4位数字)
String rand = request.getParameter("rand");
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;
} // 将认证码存入SESSION
session.setAttribute("rand",rand); // 将认证码显示到图象中
g.se
tColor(Color.black);
Integer tempNumber = new Integer(rand);
String numberStr = tempNumber.toString(); g.setFont(new Font("Atlantic Inline",Font.PLAIN,18));
String Str = numberStr.substring(0,1);
g.drawString(Str,8,17); Str = numberStr.substring(1,2);
g.drawString(Str,20,15);
Str = numberStr.substring(2,3);
g.drawString(Str,35,18); Str = numberStr.substring(3,4);
g.drawString(Str,45,15); // 随机产生88个干扰点,使图象中的认证码不易被其它程序探测到
Random random = new Random();
for (int i=0;i<20;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
g.drawOval(x,y,0,0);
} // 图象生效
g.dispose(); // 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
%>
然后在你需要调用的地方写上
<img src="img.jsp">就可以了!
我刚刚学了哈哈!
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); // 取随机产生的认证码(4位数字)
String rand = request.getParameter("rand");
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;
} // 将认证码存入SESSION
session.setAttribute("rand",rand); // 将认证码显示到图象中
g.se
tColor(Color.black);
Integer tempNumber = new Integer(rand);
String numberStr = tempNumber.toString(); g.setFont(new Font("Atlantic Inline",Font.PLAIN,18));
String Str = numberStr.substring(0,1);
g.drawString(Str,8,17); Str = numberStr.substring(1,2);
g.drawString(Str,20,15);
Str = numberStr.substring(2,3);
g.drawString(Str,35,18); Str = numberStr.substring(3,4);
g.drawString(Str,45,15); // 随机产生88个干扰点,使图象中的认证码不易被其它程序探测到
Random random = new Random();
for (int i=0;i<20;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
g.drawOval(x,y,0,0);
} // 图象生效
g.dispose(); // 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
%>
java.awt.image.*,java.util.*,javax.imageio.*" pageEncoding="gbk"%>
<%!
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=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();
// 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.PLAIN,18));
//画边框
//g.setColor(new Color());
//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=String.valueOf(random.nextInt(10));
sRand+=rand;
// 将认证码显示到图象中
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
//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,13*i+6,16);
}
// 将认证码存入SESSION
session.setAttribute("rand",sRand);
//session.setAttribute("myname","xiaoqiang");
System.out.print("生成的验证码是:"+session.getAttribute("rand")); // 图象生效
g.dispose();
// 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
out.clear();
out = pageContext.pushBody();
%>上面是验证码图片生成的JSP,并且把验证码的字符串保存到Session中,方便下面的程序判断用户输入的验证码,是否跟系统生成的一样下面是JSP引用该验证码<img alt="" src="/image.jsp"/>
之后在Action中判断就可以了