JavaScript设置cookie、读取cookie、删除cookie详解

JS设置cookie、读取cookie、删除cookie

1. JS设置cookie：

假设在A页面中要保存变量$(‘#username’).val()的值到cookie中,key值为username，则相应的JS代码为：

document.cookie = 'username =' + $('#username').val();  

例子：设置username=’aaa’的cookie

document.cookie = 'username = aaa';document.cookie="userId=828; userName=hulk";

不是覆盖 是增加：

document.cookie="userId=828";document.cookie="userName=hulk";

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2.JS读取cookie：

假设cookie中存储的内容为：username =jack;password=123

function getCookie(cookie_name){    var allcookies = document.cookie;    var cookie_pos = allcookies.indexOf(cookie_name);    if (cookie_pos != -1){        cookie_pos += cookie_name.length + 1;         var cookie_end = allcookies.indexOf(";", cookie_pos);        if (cookie_end == -1){            cookie_end = allcookies.length;        }        var value = unescape(allcookies.substring(cookie_pos, cookie_end));     }    return value;}  getCookie(username)  ==> jackgetCookie(password)  ==> 123

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3. 删除cookie：

为了删除一个cookie，可以将其过期时间设定为一个过去的时间，例如：

<script language="JavaScript" type="text/javascript">function deleteCookie(name){     //获取当前时间    var date=new Date();    //将date设置为过去的时间    date.setTime(date.getTime()-10000);    //将userId这个cookie删除    //document.cookie="userId=828; expire="+date.toGMTString();    document.cookie=name+"=v; expires="+date.toGMTString();       }      deleteCookie("aaa")   //删除aaa的cookie</script>   

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4.给cookie设置终止日期：

设置为10天后过期，可以这样实现：

<script language="JavaScript" type="text/javascript">    //获取当前时间    var date=new Date();    var expireDays=10;    //将date设置为10天以后的时间    date.setTime(date.getTime()+expireDays*24*3600*1000);    //将userId和userName两个cookie设置为10天后过期    document.cookie="userId=828; userName=hulk; expire="+date.toGMTString();</script>  

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5. 判断是否有保存用户名的cookie：

function isCookie(key) {    var strCookie = document.cookie;    strCookie = strCookie.split('; ');    for (var i = 0, l = strCookie.length; i < l; i++) {        var att = strCookie[i].split('=');        if (att[0] == key) {            return att[1]        };    };    return false}  isCookie('userId');          // 判断是否有保存userld的cookie   存在返回true， 不存在返回falseisCookie('userName');        // 判断是否有保存userName的cookie

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方法封装

//设置cookie  function setCookie(cname, cvalue, exdays) {      var d = new Date();      d.setTime(d.getTime() + (exdays*24*60*60*1000));      var expires = "expires="+d.toUTCString();      document.cookie = cname + "=" + cvalue + "; " + expires;  }  //获取cookie  function getCookie(cname) {      var name = cname + "=";      var ca = document.cookie.split(';');      for(var i=0; i<ca.length; i++) {          var c = ca[i];          while (c.charAt(0)==' ') c = c.substring(1);          if (c.indexOf(name) != -1) return c.substring(name.length, c.length);      }      return "";  }  //清除cookie    function clearCookie(name) {        setCookie(name, "", -1);    } 

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jquery.cookie.js 插件

插件地址：http://apps.bdimg.com/libs/jquery.cookie/1.4.1/jquery.cookie.js

/**记住帐号密码**/if ($("#checkbox").is(":checked")) {    $.cookie("rmbUser", "true", {        expires: 7    }); //存储一个带7天期限的cookie    $.cookie("username", userName, {        expires: 7    });    $.cookie("password", userPwd, {        expires: 7    });} else {    $.cookie("rmbUser", "false", {        expire: -1    });    $.cookie("username", "", {        expires: -1    });    $.cookie("password", "", {        expires: -1    });}  

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调用模版

//设置cookie    function setCookie(name, value, seconds) {        seconds = seconds || 0;   //seconds有值就直接赋值，没有为0，这个根php不一样。        var expires = "";        if (seconds != 0 ) {      //设置cookie生存时间            var date = new Date();            date.setTime(date.getTime()+(seconds*1000));            expires = "; expires="+date.toGMTString();        }        document.cookie = name+"="+escape(value)+expires+"; path=/";   //转码并赋值    }   //取得cookie    function getCookie(name) {        var nameEQ = name + "=";        var ca = document.cookie.split(';');    //把cookie分割成组        for(var i=0;i < ca.length;i++) {            var c = ca[i];                      //取得字符串            while (c.charAt(0)==' ') {          //判断一下字符串有没有前导空格                c = c.substring(1,c.length);      //有的话，从第二位开始取            }            if (c.indexOf(nameEQ) == 0) {       //如果含有我们要的name                return unescape(c.substring(nameEQ.length,c.length));    //解码并截取我们要值            }        }        return false;    }    //清除cookie    function clearCookie(name) {        setCookie(name, "", -1);    } //调用一下上面方法：   setCookie("test","tank",1800);   //设置cookie的值，生存时间半个小时    alert(getCookie('test'));        //取得cookie的值，显示tank    clearCookie("test");             //删除cookie的值    alert(getCookie('test'));        //test对应的cookie值为空，显示为false.就是getCookie最后返的false值。