Num.jsp
<%@ page contentType="image/jpeg" import="java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*" %><%!
??? Color getRandColor(int cc,int bb)
??? {
??????? Random random = new Random();
??????? if(fc>255) cc=255;
??????? if(bc>255) bb=255;
??????? int r=cc+random.nextInt(bb-cc);
??????? int g=cc+random.nextInt(bb-cc);
??????? int b=cc+random.nextInt(bb-cc);
??????? returnnew Color(r,g,b);
??? } //獲取隨機顏色
%>
<%
??? response.setHeader("Pragma","No-cache");
??? response.setHeader("Cache-Control","no-cache");
??? response.setDateHeader("Expires", 0);
?
??? int width=80; //定義驗證碼圖片的長度
??? int height=30; //定義驗證碼圖片的寬度
??? BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
?
??? Graphics g = image.getGraphics();
?
??? Random random = new Random();
?
??? g.setColor(getRandColor(200,250));
??? g.fillRect(0, 0, width, height);
?
??? g.setFont(new Font("Times New Roman",Font.PLAIN,18));
????//定義字體形式
?
??? g.setColor(getRandColor(160,200));
??? for (int i=0;i<155;i++)
??? {
?????? int i_x = random.nextInt(width);
?????? int i_y = random.nextInt(height);
?????? int i_xl = random.nextInt(12);
?????? int i_yl = random.nextInt(12);
?????? g.drawLine(i_x,i_y,i_x+i_xl,i_y+i_yl);
??? }
??? //用線條畫背景
?
??? String s_Rand="";
??? for (int i=0;i<4;i++)
??? {
?????? String rand=String.valueOf(random.nextInt(10));
?????? s_Rand+=rand;
??????
?????? g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
?????? g.drawString(rand,13*i+6,16);
??? }
????//產生4位隨機碼?
?
??? session.setAttribute("rand",s_Rand);
????//將驗證碼存入Session中
?
??? g.dispose();
???
??? ImageIO.write(image, "JPEG", response.getOutputStream());
????//輸出驗證圖片
???
??? out.clear();
??? out = pageContext.pushBody();
???
%>