<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<style type="text/css">
body {
    background-color: pink;
}

form {
    margin-top: 100px;
    margin-left: 100px;
}
img{
   height-line:20px;
   height:20px;
   width:20px;
}
</style>
 <script type="text/javascript">
 function mycheck() {
 //判断用户名是否为空
 if (form1.userName.value==""){
alert("用户名不能为空，请输入用户名！");
 form1.userName.focus();
 return;
 }
 //判断密码是否为空
 if (form1.password.value=="") {
 alert("密码不能为空，请输入密码！");
 form1.password.focus();
 return;
 }
//判断验证码是否为空
 if (form1.validationCode.value==""){
alert("验证码不能为空，请输入验证码!");
 form1.validationCode.focus();
 return;
 }
 //判断验证码是否正确
 if (form1.validationCode.value != form1.validationCode1.value) {
 alert("请输入正确的验证码!!");
 form1.validationCode.focus();
 return;
 }
 form1.submit1();
 }
 </script>
<base href="<%=basePath%>">

<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
</head>

<body>
    <form action="LoginCheck.jsp" method="get">
        用 户 名：<input type="text" name="userName" size="18"><br><br>
        密     码：<input type="password" name="password" size="18"> <br><br>
        验 证 码：<input type="text" name="validationCode"
            onKeyDown="if(event.keyCode==13){form1.submit.focus();}" size="6">
        <%
            int intmethod1 = (int) ((((Math.random()) * 11)) - 1);
            int intmethod2 = (int) ((((Math.random()) * 11)) - 1);
            int intmethod3 = (int) ((((Math.random()) * 11)) - 1);
            int intmethod4 = (int) ((((Math.random()) * 11)) - 1);
            //将得到的随机数进行连接
            String intsum = intmethod1 + "" + intmethod2 + intmethod3
                    + intmethod4;
        %>
        <!-- 设置隐藏域,验证比较时使用-->
        <input type="hidden" name="validationCode1" value="<%=intsum%>">
        <!-- 将图片名称与得到的随机数相同的图片显示在页面上 -->
        <img src="./img/<%=intmethod1%>.jpg"> <img src="./img/<%=intmethod2%>.jpg">
        <img src="./img/<%=intmethod3%>.jpg"> <img src="./img/<%=intmethod4%>.jpg"><br><br>  
        <input type="submit" name="submit1" value="登录"
            onClick="mycheck()">   <input type="reset" value="重置">
    </form>
    </form>

</body>
</html>