<%@ page contentType="text/html;charset=GB2312"%>
<HTML>
<BODY bgcolor=cyan>
<p>请输入圆的半径:</p>
<BR>
<form name="theform" action="" method="GET">
<input type="text" size="5" name="input1">
<input type="SUBMIT" name="submit" value="计算">
</form>
<%!
class Circle{
double r;
Circle(double r){
this.r=r;
}
public double 求面积(){
return Math.PI*r*r;
}
public double 求周长(){
return Math.PI*2*r;
}
}
%>
<%
String s=request.getParameter("input1");
float f=0f;
try{
f=Float.parseFloat(s);
}
catch(NumberFormatException e){
System.out.print("请输入数字字符");
}
Circle circle=new Circle(f);
%>
<p>圆的面积是:
<BR>
<%=circle.求面积()%></p>
<p>圆的周长是:
<BR>
<%=circle.求周长()%></p>
</BODY>
</HTML>
运行不了
<HTML>
<BODY bgcolor=cyan>
<p>请输入圆的半径:</p>
<BR>
<form name="theform" action="" method="GET">
<input type="text" size="5" name="input1">
<input type="SUBMIT" name="submit" value="计算">
</form>
<%!
class Circle{
double r;
Circle(double r){
this.r=r;
}
public double 求面积(){
return Math.PI*r*r;
}
public double 求周长(){
return Math.PI*2*r;
}
}
%>
<%
String s=request.getParameter("input1");
float f=0f;
try{
f=Float.parseFloat(s);
}
catch(NumberFormatException e){
System.out.print("请输入数字字符");
}
Circle circle=new Circle(f);
%>
<p>圆的面积是:
<BR>
<%=circle.求面积()%></p>
<p>圆的周长是:
<BR>
<%=circle.求周长()%></p>
</BODY>
</HTML>
运行不了
楼主【wongshiang】截止到2008-07-18 00:32:09的历史汇总数据(不包括此帖):
发帖的总数量:6 发帖的总分数:100 每贴平均分数:16
回帖的总数量:10 得分贴总数量:0 回帖的得分率:0%
结贴的总数量:3 结贴的总分数:40
无满意结贴数:1 无满意结贴分:20
未结的帖子数:3 未结的总分数:60
结贴的百分比:50.00 % 结分的百分比:40.00 %
无满意结贴率:33.33 % 无满意结分率:50.00 %
楼主加油
action没有写 往哪里提交啊
<%@ page contentType="text/html;charset=GB2312" pageEncoding="GB2312"%>
<HTML>
<BODY bgcolor=cyan>
<p>请输入圆的半径:</p>
<BR>
<form name="theform" action="" method="GET"><input type="text"
size="5" name="input1"> <input type="SUBMIT" name="submit"
value="计算"></form>
<%!class Circle {
double r; Circle(double r) {
this.r = r;
} public double 求面积() {
return Math.PI * r * r;
} public double 求周长() {
return Math.PI * 2 * r;
}
}%>
<%
String s = request.getParameter("input1");
if (s == null)
s = "0";
float f = 0f;
try {
f = Float.parseFloat(s);
} catch (NumberFormatException e) {
System.out.print("请输入数字字符");
}
Circle circle = new Circle(f);
%>
<p>圆的面积是: <BR>
<%=circle.求面积()%></p>
<p>圆的周长是: <BR>
<%=circle.求周长()%></p>
</BODY>
</HTML>
double r; Circle(double r) {
this.r = r;
} public double 求面积() {
return Math.PI * r * r;
} public double 求周长() {
return Math.PI * 2 * r;
}
}%>
单独写一个类文件中,jsp import进来。
<%@ page import="com.yyzt.test.Circle" %><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
</head>
<body>
<form name="theform" action="" method="GET"><input type="text"
size="5" name="input1"> <input type="submit" name="submit"
value="计算"></form>
<%
String s = request.getParameter("input1");
if (s == null||s.equals(""))
s = "0";
double d = 0.0;
try {
d = Double.parseDouble(s);
} catch (NumberFormatException e) {
out.println("e.getMessage="+e.getMessage());
out.print("请输入数字字符");
}
Circle circle = new Circle(d);
%>
<p>圆的面积是: <BR>
<%=circle.countArea()%></p>
<p>圆的周长是: <BR>
<%=circle.countGirth()%></p>
</body>
</html>
package com.yyzt.test;public class Circle {
double r=0.0; public Circle(double r) {
this.r = r;
} public double countArea() {
return Math.PI * r * r;
} public double countGirth() {
return Math.PI * 2 * r;
}}
<%@ page contentType="text/html;charset=GB2312"%>
<HTML>
<BODY bgcolor=cyan>
<p>请输入圆的半径: </p>
<BR>
<form name="theform" action="" method="GET">
<input type="text" size="5" name="input">
<input type="SUBMIT" name="submit" value="计算">
</form>
<%!
class Circle{
double r;
Circle(double r){
this.r=r;
}
public double 求面积(){
return Math.PI*r*r;
}
public double 求周长(){
return Math.PI*2*r;
}
}
%>
<%
String s=request.getParameter("input")==null?"":request.getParameter("input");
float f=0f;
try{
f=Float.parseFloat(s);
}
catch(NumberFormatException e){
System.out.print("请输入数字字符");
}
Circle circle=new Circle(f);
%>
<p>圆的面积是:
<BR>
<%=circle.求面积()%> </p>
<p>圆的周长是:
<BR>
<%=circle.求周长()%> </p>
</BODY>
</HTML>
<%@ page contentType="text/html;charset=GB2312"%>
<HTML>
<BODY bgcolor=cyan>
<p>请输入圆的半径: </p>
<BR>
<form name="theform" action="" method="GET">
<input type="text" size="5" name="input">
<input type="SUBMIT" name="submit" value="计算">
</form>
<%!
class Circle{
double r;
Circle(double r){
this.r=r;
}
public double 求面积(){
return Math.PI*r*r;
}
public double 求周长(){
return Math.PI*2*r;
}
}
%>
<%
String s=request.getParameter("input")==null?"":request.getParameter("input");
float f=0f;
try{
f=Float.parseFloat(s);
}
catch(NumberFormatException e){
System.out.print("请输入数字字符");
}
Circle circle=new Circle(f);
%>
<p>圆的面积是:
<BR>
<%=circle.求面积()%> </p>
<p>圆的周长是:
<BR>
<%=circle.求周长()%> </p>
</BODY>
</HTML>