前言
使用<jsp:include/>动作标记在JSP页面中动态插入一个文件、使用<jsp:forward/>动作标记在JSP页面中实现跳转。
实验内容1
include动作标记：编写三个JSP页面，main.jsp，ladder.jsp和circle.jsp页面，将三个JSP页面保存在同一个WEB服务目录中，main.jsp页面中使用include动作标记动态插入ladder.jsp和circle.jsp页面分别计算梯形和圆形的面积。并且ladder.jsp和circle.jsp页面运行时分别获取include动作标记的param子标记传递过来的上底、下底和高以及圆半径的值。代码
- main.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>计算页面</title>
</head>
<body>
<% double r=2,a=3,b=5,h=4; %>
<BR>加载circle.jsp半径为
<Font color=blue size=4>
<%=r%>
</Font>
的圆的面积：
<jsp:include page="circle.jsp">
<jsp:param name="circle" value="<%=r%>" /> </jsp:include>
<BR>加载ladder.jsp各参数为
<Font color=blue size=4>
<%=a%>,
<%=b%>,
<%=h%>
</Font>
的梯形的面积：
<jsp:include page="ladder.jsp">
<jsp:param name="SDi" value="<%=a%>" />
<jsp:param name="XDi" value="<%=b%>" />
<jsp:param name="height" value="<%=h%>" /> </jsp:include>
</body>
</html>
- ladder.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>梯形面积</title>
</head>
<body>
<%! public String getArea(double a,double b,double h)
{
double area=(a+b)*h/2;
return ""+area;
} %>
<% String SDi=request.getParameter("SDi");
String XDi=request.getParameter("XDi");
String height=request.getParameter("height");
double a=Double.parseDouble(SDi);
double b=Double.parseDouble(XDi);
double h=Double.parseDouble(height);
%>
<Font color=blue size=4>
<%= getArea(a,b,h)%>
</Font>
</body>
</html>
- circle.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>圆形面积</title>
</head>
<body>
<%! public String getArea(double r){
double n=3.14*r*r;
return ""+n;
}
%>
<% String circle=request.getParameter("circle");
double r= Double.parseDouble(circle);
%>
<Font color=blue size=4>
<%=getArea(r)%>
</Font>
</body>
</html>
实验内容2
这个实验内容要求太多了。总结起来要实现的功能就是：在one.jsp页面判断，用户在表单输入1~100之间的整数，提交给页面。判断如果在1~50就转向two.jsp；51~100就转向three.jsp；不合要求转向error.jsp（每个页面都包含一个head.txt的导航页）代码
- one.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>include标记</title>
<jsp:include page="head.txt" />
</head>
<body bgcolor=yellow>
<form action="" method="GET" name="form">
请输入1~100之间的整数：<input type="text" name="number">
<br/> <input type="submit" value="送出" name="submit">
</form>
<% String num=request.getParameter("number");
if(num==null)
num="0";
try{
int n=Integer.parseInt(num);
if(n>=1 && n<=50){
%>
<jsp:forward page="two.jsp">
<jsp:param name="number" value="<%=n%>" />
</jsp:forward>
<% }
else if(n>50 && n<= 100){
%>
<jsp:forward page="three.jsp">
<jsp:param name="number" value="<%=n%>" />
</jsp:forward>
<% }
else if(n>100){
%>
<jsp:forward page="error.jsp">
<jsp:param name="mess" value="<%=n%>" />
</jsp:forward>
<% }
}
catch(Exception e){
%>
<jsp:forward page="error.jsp">
<jsp:param name="mess" value="<%=e.toString()%>" />
</jsp:forward>
<% }
%>
</body>
</html>
- two.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>two</title>
<jsp:include page="head.txt" />
</head>
<body bgcolor=yellow>
<p>
<font size="3" color=blue>this is two.jsp</font>
<font size=3>
<% String s=request.getParameter("number");
out.println("<br/>传过来的值是" + s);
%>
<br/><img src="a.jpg" width="<%=s%>" height="<%=s%>"></img>
</font>
</p>
</body>
</html>
- three.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>three</title>
<jsp:include page="head.txt" />
</head>
<body>
<body bgcolor=yellow>
<p>
<font size="3" color=red>this is three.jsp</font>
<font size=3>
<% String s=request.getParameter("number");
out.println("<br/>传过来的值是" + s);
%>
<br/><img src="b.jpg" width="<%=s%>" height="<%=s%>"></img>
</font>
</p>
</body>
</html>
- error.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>error</title>
<jsp:include page="head.txt" />
</head>
<body>
<body bgcolor=yellow>
<p>
<font size="5" color=red>this is error.jsp</font>
<font size=3>
<% String s=request.getParameter("mess");
out.println("<br/>传过来的错误信息是" + s);
%>
<br/><img src="error.jpg" width="120" height="120"></img>
</font>
</p>
</body>
</html>
- head.txt
<table cellSpacing="1" cellPadding="1" width="60%" align="center" border="0">
<tr valign="bottom">
<td><a href="one.jsp"><font size=3>one.jsp</font></a></td>
<td><a href="two.jsp"><font size=3>two.jsp</font></a></td>
<td><a href="error.jsp"><font size=3>error.jsp</font></a></td>
</tr>
</table>实验内容3
创建一个login.jsp文件，提交表单页面至当前页面，判断用户选择的用户类型，如果是管理员则使用forward动作标记跳转至admins.jsp页面，在admins.jsp页面判断如果管理员用户名是admin并且密码也是admin,则输出管理员登录成功！判断用户选择的用户类型，如果是普通用户则使用forward动作标记跳转至users.jsp页面，在users.jsp页面判断如果普通用户用户名是web并且密码是jsp，则输出会员登录成功！代码
- ligin.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>用户登录</title>
</head>
<body>
<br/>
<form action="">
<table border="0" width="500px">
<tr>
<td>用户名:</td>
<td><input type="text" name="username" /></td>
</tr>
<tr>
<td>口令:</td>
<td> <input type="password" name="password" /></td>
</tr>
<tr>
<td>用户类型:</td>
<td> <input type="radio" name="a" value="admin">管理员
</td>
<td> <input type="radio" name="a" value="user">普通用户</td>
</tr>
<tr>
<td><input type="submit" value="登录" /></td>
<td><input type="reset" value="重置" /></td>
</tr>
</table>
</form>
<%
request.setCharacterEncoding("UTF-8");
String str = request.getParameter("a");
String username = request.getParameter("username");
String password = request.getParameter("password");
System.out.println(str);
System.out.println(username);
System.out.println(password);
if(str!=null&&username!=null&&password!=null){
if(str.equals("admin")){
%>
<jsp:forward page="admins.jsp">
<jsp:param value="<%= username %>" name="username" />
<jsp:param value="<%= password %>" name="password" />
</jsp:forward>
<%
}else{
%>
<jsp:forward page="user.jsp">
<jsp:param value="<%= username %>" name="username" />
<jsp:param value="<%= password %>" name="password" />
</jsp:forward>
<%
}
}
%>
</body>
</html>
- admins.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head>
<title>管理界面</title>
</head>
<body>
<h2>
<%
request.setCharacterEncoding("UTF-8");
String username = request.getParameter("username");
String password = request.getParameter("password");
if(username.equals("admin")&&password.equals("admin")){
out.write("管理员登录成功");
}else{
out.write("管理员登录失败");
}
%>
</h2>
</body>
</html>
- user.jsp
<%@ page language="java" import="java.util.*" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<html>
<head></head>
<body>
<h2>
<%
request.setCharacterEncoding("UTF-8");
String username = request.getParameter("username");
String password = request.getParameter("password");
if(username.equals("web")&&password.equals("jsp")){
out.write("普通用户登录成功");
}else{
out.write("普通用户登录失败");
}
%>
</h2>
</body>
</html>
