Without further ado, the specific code is as follows:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="java.util.*" %>
<%@ page import="java.sql.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title> The form submission </title>
</head>
<body>
<p align="center"><b> The form submission </b><br></p>
<center>
<div align="left">
<table height="60" border="0" align="left">
<tr>
<td>
<form name="channelform" action="addChannel.jsp"
onsubmit="return validate_channel_info(this);" method="post">
The name :
<input type="text" name="channelname" />
<br />
ID:
<input type="text" name="channelid" />
<br />
<input type="submit" value=" submit ">
</form>
</td>
</tr>
</table>
<script type="text/javascript">
function validate_channel_info(channelform)
{
if(channelform.channelname.value=="")
{
alert(" Please enter the correct name ");
return false;
}
else if(!isNumber(channelform.channelid.value))
{
alert(" Please enter legal ID");
return false;
}
return true;
}
function isNumber(str) // Determine if it is a non-negative integer
{
var rx = /^[0-9]+$/;
return rx.test(str);
}
</script>
</div>
</center>
</body>
</html>