封装cookie组件

var Cookie = {
    // 读取
     get: function(name){
        var cookieStr = "; "+document.cookie+"; ";
        var index = cookieStr.indexOf("; "+name+"=");
        if (index!=-1){
            var s = cookieStr.substring(index+name.length+3,cookieStr.length);
            return unescape(s.substring(0, s.indexOf("; ")));
        }else{
            return null;
        }
    },
    // 设置
     set : function(name,value,expires){
        var expDays = expires*24*60*60*1000;
        var expDate = new Date();
        expDate.setTime(expDate.getTime()+expDays);
        var expString = expires ? "expires="+expDate.toGMTString() : "";
        var pathString = ";path=/";
        document.cookie = name + "=" + escape(value) + expString + pathString;
    },
    // 删除
     del : function(name){
        var exp = new Date(new Date().getTime()-1);
        var s=this.read(name);
        if(s!=null) {
            document.cookie= name + "="+s+"expires="+exp.toGMTString()+";path=/"
        }
    }
};
// demo:
Cookie.set("xxx", "xx", 7);
alert(Cookie.get("xxx"));
Cookie.del("xxx");