jQuery cookie记住用户名密码自动登录

1、导入两个js文件

  1)、jquery-1.4.js

  2)、jquery.cookie.js

2、login.jsp页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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">
<meta name="viewport"
    content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />

<script type="text/javascript"
    src="${pageContext.request.contextPath}/js/jquery-1.4.js"></script>
<script type="text/javascript"
    src="${pageContext.request.contextPath}/js/jquery.cookie.js"></script>
<script type="text/javascript">

    function addCookie(name, value, days, path) {
        /**添加设置cookie**/
        var name = escape(name);
        var value = escape(value);
        var expires = new Date();
        //设置cookie保存的时间
        expires.setTime(expires.getTime() + days * 3600000 * 24);
        //path=/,表示cookie能在整个网站下使用,path=/temp,表示cookie只能在temp目录下使用  
        path = path == "" ? "" : ";path=" + path;
        //GMT(Greenwich Mean Time)是格林尼治平时,现在的标准时间,协调世界时是UTC  
        //参数days只能是数字型  
        var _expires = (typeof days) == "string" ? "" : ";expires="
                + expires.toUTCString();
        document.cookie = name + "=" + value + _expires + path;
    }
    function getCookieValue(name) {
        /**获取cookie的值,根据cookie的键获取值**/
        //用处理字符串的方式查找到key对应value  
        var name = escape(name);
        //读cookie属性,这将返回文档的所有cookie  
        var allcookies = document.cookie;
        //查找名为name的cookie的开始位置  
        name += "=";
        var pos = allcookies.indexOf(name);
        //如果找到了具有该名字的cookie,那么提取并使用它的值  
        if (pos != -1) { //如果pos值为-1则说明搜索"version="失败  
            var start = pos + name.length; //cookie值开始的位置  
            var end = allcookies.indexOf(";", start); //从cookie值开始的位置起搜索第一个";"的位置,即cookie值结尾的位置  
            if (end == -1)
                end = allcookies.length; //如果end值为-1说明cookie列表里只有一个cookie  
            var value = allcookies.substring(start, end); //提取cookie的值  
            return (value); //对它解码        
        } else { //搜索失败,返回空字符串  
            return "";
        }
    }
    function deleteCookie(name, path) {
        /**根据cookie的键,删除cookie,其实就是设置其失效**/
        var name = escape(name);
        var expires = new Date(0);
        path = path == "" ? "" : ";path=" + path;
        document.cookie = name + "=" + ";expires=" + expires.toUTCString()
                + path;
    }

    /**实现功能,保存用户的登录信息到cookie中。当登录页面被打开时,就查询cookie**/
    window.onload = function(){
        //获取cookie中存放的用户名
        var userNameValue = getCookieValue("userName");
        document.getElementById("userName").value = userNameValue;
        //获取cookie中存放的密码
        var userPassValue = getCookieValue("userPass");
        document.getElementById("password").value = userPassValue;
        //如果账号密码为空则弹出提示,输入用户名密码
        if(userNameValue==""&&userPassValue==""){    
            $("input[name='userName']").focus();
        //如果账号密码不为空则直接执行登录    
        }else if(userNameValue!=""&&userPassValue!=""){
        
        var vdata = {
                userName : userNameValue,
                password : userPassValue
            };

            $.post("tevo_loginInit.action", vdata, function(data) {
                if (data == "succ") {
                    $(".login_info").show();
                    $(".login_info").html("&nbsp;&nbsp;正在登录中...");
                    location.href = "main.action";
                } else if (data == "error1") {
                    alert("用户未分配角色或权限!");
                } else if (data == "error2") {
                    alert("用户无效!");
                } else if (data == "error3") {
                    alert("用户未分配角色!");
                } else if (data == "error4") {
                    alert("用户角色未分配权限!");
                } else if (data == "error5") {
                    alert("用户所分配权限未分配功能!");
                } else {
                    alert("用户名或者密码错误,请重新输入!");
                }
            });
        }
        
    };
    // 回车登录
    function keyLogin() {
        $("input[name='userName']").keydown(function(event) {
            var event = arguments.callee.caller.arguments[0] || window.event;// 消除浏览器差异
            if (event.keyCode == 13) {
                $("input[name='password']").focus();
            }
        });
        $("input[name='password']").keydown(function(event) {
            if (event.keyCode == 13) {
                userLogin();
                document.getElementByIdx_x("userLogin").click();
            }
        });

    }
    
    function userLogin() {
        /**用户登录,其中需要判断是否选择记住密码**/
        //简单验证一下  
        var userName = document.getElementById("userName").value;
        if (userName == '') {
            alert("请输入用户名!");
            return;
        }
        var userPass = document.getElementById("password").value;
        if (userPass == '') {
            alert("请输入密码!");
            return;
        }
        var objChk = document.getElementById("chkRememberPass");
        if (objChk.checked) {
            //添加cookie  
            addCookie("userName", userName, 365, "/");
            addCookie("userPass", userPass, 365, "/");

            var vuserName = $("#userName").val();
            var vpassword = $("#password").val();

            if (vuserName == "" || vuserName == undefined || vuserName == null) {
                alert("用户名不能为空");
                return false;
            } else if (vpassword == "" || vpassword == undefined
                    || vpassword == null) {
                alert("密码不能为空");
                return false;
            }
    
            var vdata = {
                userName : vuserName,
                password : vpassword
            };

            $.post("tevo_loginInit.action", vdata, function(data) {
                if (data == "succ") {
                    $(".login_info").show();
                    $(".login_info").html("&nbsp;&nbsp;正在登录中...");
                    location.href = "main.action";
                } else if (data == "error1") {
                    alert("用户未分配角色或权限!");
                } else if (data == "error2") {
                    alert("用户无效!");
                } else {
                    alert("用户名或者密码错误,请重新输入!");
                }
            });
        } else {

            //删除cookie的内容
            deleteCookie("userName", "/");
            deleteCookie("userPass", "/");
            var vuserName = $("#userName").val();
            var vpassword = $("#password").val();

            if (vuserName == "" || vuserName == undefined || vuserName == null) {
                alert("用户名不能为空");
                return false;
            } else if (vpassword == "" || vpassword == undefined
                    || vpassword == null) {
                alert("密码不能为空");
                return false;
            }

            var vdata = {
                userName : vuserName,
                password : vpassword
            };

            $.post("tevo_loginInit.action", vdata, function(data) {
                if (data == "succ") {

                    $(".login_info").show();
                    $(".login_info").html("&nbsp;&nbsp;正在登录中...");
                    location.href = "main.action";
                } else if (data == "error1") {
                    alert("用户未分配角色或权限!");
                } else if (data == "error2") {
                    alert("用户无效!");
                } else {
                    alert("用户名或者密码错误,请重新输入!");
                }
            });
        }
    }
</script>
<title>登录</title>
<style type="text/css">
.center-in-center {
    position: absolute;
    top: 50%;
    left: 50%;
}
</style>
</head>

<body background="${pageContext.request.contextPath}/images/login.jpg"
    onkeydown="keyLogin();">

    <div class="center-in-center">
        <form id="login">
            用户名:&nbsp;&nbsp;<input type="text" name="userName" id="userName"
                placeholder="请输入用户名" /><br />
            <br /> &nbsp;密码:&nbsp;&nbsp;&nbsp;&nbsp;<input type="password"
                name="password" id="password" placeholder="请输入密码" /> <br />
            <br /> <br /> <input type="checkbox" id="chkRememberPass"
                name="chkRememberPass" style="vertical-align:middle;"
                checked="checked" /> <span
                style="font-size:12px; color:blue; vertical-align:middle;">记住密码</span>
            <br />
            <br />
            <div align="center">
                &nbsp;&nbsp;&nbsp;&nbsp;<input type="button" id="login"
                    onclick="userLogin()" value="登录" />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <input type="reset" value="重置" />
            </div>
            <br />
            <div class="login_info" style="display:none;"></div>
            <div class="login_info2">&nbsp;&nbsp;</div>
        </form>
    </div>
</body>
</html>
原文地址:https://www.cnblogs.com/shoose/p/8393735.html