JSP常用功能模块
JSP常用功能模块
显示任意年、月并可选择不同的年、月的日历程序calendar.jsp
| <!-- author:wildfield --> <%@ page language="java" import="java.util.*" %> <%! String year; String month; %> <% month=request.getParameter("month"); year =request.getParameter("year"); %> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <title>日</title> <script Language="javascript"> <!-- function changeMonth() { var mm="calendar.jsp?month="+document.sm.elements[0].selectedIndex+"&year=" +<%=year%>; window.open(mm,"_self"); } //--> </script> </head> <%! String days[]; %> <% days=new String[42]; for(int i=0;i<42;i++) { days=""; } %> <% Calendar thisMonth=Calendar.getInstance(); if(month!=null&&(!month.equals("null"))) thisMonth.set(Calendar.MONTH, Integer.parseInt(month) ); if(year!=null&&(!year.equals("null"))) thisMonth.set(Calendar.YEAR, Integer.parseInt(year) ); year=String.valueOf(thisMonth.get(Calendar.YEAR)); month=String.valueOf(thisMonth.get(Calendar.MONTH)); thisMonth.setFirstDayOfWeek(Calendar.SUNDAY); thisMonth.set(Calendar.DAY_OF_MONTH,1); int firstIndex=thisMonth.get(Calendar.DAY_OF_WEEK)-1; int maxIndex=thisMonth.getActualMaximum(Calendar.DAY_OF_MONTH); for(int i=0;i<maxIndex;i++) { days[firstIndex+i]=String.valueOf(i+1); } %> <body> <FORM name="sm" method="post" action="calendar.jsp"> <%=year%>年 <%=Integer.parseInt(month)+1%>月 <table width="168" height="81"> <div align=center> <tr> <th width="25" height="16" bgcolor="#FFFF00"><font color="red">日</font> </th> <th width="25" height="16" bgcolor="#FFFF00">一</th> <th width="25" height="16" bgcolor="#FFFF00">二</th> <th width="25" height="16" bgcolor="#FFFF00">三</th> <th width="25" height="16" bgcolor="#FFFF00">四</th> <th width="25" height="16" bgcolor="#FFFF00">五</th> <th width="25" height="16" bgcolor="#FFFF00"><font color="green">六</font></th> </tr> <% for(int j=0;j<6;j++) { %> <tr> <% for(int i=j*7;i<(j+1)*7;i++) { %> <td width="15%" height="16" bgcolor="#C0C0C0" valign="middle" align="center"> <a href="jump.jsp?year=<%=year%>&month=<%=Integer.parseInt(month)+1%>&date=<%=days[i]%>" target="main"><%=days[i]%></a></td> <% } %> </tr> <% } %> </div> </table> <table width="168" height="20"> <tr> <td width=30%><select name="month" size="1" onchange="changeMonth()" > <option value="0">一月</option> <option value="1">二月</option> <option value="2">三月</option> <option value="3">四月</option> <option value="4">五月</option> <option value="5">六月</option> <option value="6">七月</option> <option value="7">八月</option> <option value="8">九月</option> <option value="9">十月</option> <option value="10">十一月</option> <option value="11">十二月</option> </select></td> <td width=28%><input type=text name="year" value=<%=year%> size=4 maxlength=4></td> <td>年</td> <td width=28%><input type=submit value="提交"></td> </tr> </table> </FORM> <script Language="javascript"> <!-- document.sm.month.options.selectedIndex=<%=month%>; //--> </script> </body> </html> |
JSP生成彩色验证码程序
生成有4个随机数字和杂乱背景的图片，数字和背景颜色会改变，服务器端刷新（用history.go(-1)也会变）
产生验证码图片的文件image.jsp
| <%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*" %> <%! 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); // 图象生效 g.dispose(); // 输出图象到页面 ImageIO.write(image, "JPEG", response.getOutputStream()); %> |
使用验证码图片的文件a.jsp
| <%@ page contentType="text/html;charset=gb2312" %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>认证码输入页面</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META HTTP-EQUIV="Pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT="no-cache"> <META HTTP-EQUIV="Expires" CONTENT="0"> </head> <body> <form method=post action="check.jsp"> <table> <tr> <td align=left>系统产生的认证码：</td> <td><img image.jsp"></td> </tr> <tr> <td align=left>输入上面的认证码：</td> <td><input type=text name=rand maxlength=4 value=""></td> </tr> <tr> <td colspan=2 align=center><input type=submit value="提交检测"></td> </tr> </form> </body> </html> |
验证的页面check.jsp
| <%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %> <html> <head> <title>认证码验证页面</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META HTTP-EQUIV="Pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT="no-cache"> <META HTTP-EQUIV="Expires" CONTENT="0"> </head> <body> <% String rand = (String)session.getAttribute("rand"); String input = request.getParameter("rand"); %> 系统产生的认证码为： <%= rand %><br> 您输入的认证码为： <%= input %><br> <br> <% if (rand.equals(input)) { %> <font color=green>输入相同，认证成功！</font> <% } else { %> <font color=red>输入不同，认证失败！</font> <% } %> </body> </html> |