一共是两个页面文件：
1、input.html文件，主要是向显示页面并且向页面输入和提交输入的信息；
input.html
1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2 <html> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5 <title>input</title> 6 <script type="text/javascript" language="javascript"> 7 function validate(f){ 8 if(document.form1.info.value == "" || document.form1.info.value==null ){ 9 window.alert("Input is Null! Please input some infomation……"); 10 f.info.focus() 11 return false; 12 } 13 14 } 15 </script> 16 </head> 17 <body> 18 19 <form id="form1" name="form1" method = "post" action="input.jsp" onSubmit="return validate(this)"> 20 The Input informations:<input type="text" name="info"/> 21 <input type="submit" value="Show"/> 22 </form> 23 </body> 24 </html>
2、input.jsp文件，主要是为了处理有HTML提交来的信息，并且再把处理的结果返回给html。
input.jsp
1 <%@ page language="java" contentType="text/html; charset=ISO-8859-1" 2 pageEncoding="ISO-8859-1"%> 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 4 <html> 5 <head> 6 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> 7 <title>Insert title here</title> 8 </head> 9 <body> 10 <% 11 String str = request.getParameter("info"); 12 out.println("The Input informations:"+"<h1>"+str+"</h1>"); 13 %> 14 15 </body> 16 </html>