JSP提供了Java的全部功能可以嵌入在Web应用程序。可以使用Java的所有API和构建块在JSP编程。
if … else
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>if-else</title>
</head>
<body>
<% int num = 1; %>
<%
if(num==1){
out.print("成功");
}else{
out.print("失败");
}
%>
</body>
</html>
或
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>if-else</title>
</head>
<body>
<% int num = 1; %>
<%
<% if(num==3){%>
<p>11111111111</p>
<%}else{ %>
<p>22222222</p>
<%} %>
</body>
</html>
效果图
上面我使用了两种方式编写，下面我就采用第二种方式编写
switch…case
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>switch...case</title>
</head>
<body>
<% int num = 0; %>
<%
switch(num){
case 0:
out.print("星期日");
break;
case 1:
out.print("星期一");
break;
case 2:
out.print("星期二");
break;
case 3:
out.print("星期三");
break;
case 4:
out.print("星期四");
break;
case 5:
out.print("星期五");
break;
case 6:
out.print("星期六");
break;
}
%>
</body>
</html>
效果图：
for循环
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>for循环</title>
</head>
<body>
<%for(int num = 1;num<10;num++){ %>
<font color="red" size="<%=num %>">
这是数字<%=num %>
</font><br/>
<% }%>
</body>
</html>
效果图:
while循环
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>while循环</title>
</head>
<body>
<%
int num = 0;
while(num <= 5){
out.println("这里是测试数据"+num+"\n");
num++;
}
%>
</body>
</html>
效果图:
do-while循环
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>do-while循环</title>
</head>
<body>
<%
int num = 0;
do{
out.print("这是第"+num+"条测试数据") ;
num++;
}while(num<=5);
%>
</body>
</html>
效果图: