JS读写COOKIE的方法

var Cookies = {};

Cookies.set = function(name, value){

     var argv = arguments;

     var argc = arguments.length;

     var expires = (argc > 2) ? argv[2] : null;

     var path = (argc > 3) ? argv[3] : '/';

     var domain = (argc > 4) ? argv[4] : null;

     var secure = (argc > 5) ? argv[5] : false;

     document.cookie = name + "=" + escape (value) +

       ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +

       ((path == null) ? "" : ("; path=" + path)) +

       ((domain == null) ? "" : ("; domain=" + domain)) +

       ((secure == true) ? "; secure" : "");

};

Cookies.get = function(name){

    var arg = name + "=";

    var alen = arg.length;

    var clen = document.cookie.length;

    var i = 0;

    var j = 0;

    while(i < clen){

        j = i + alen;

        if (document.cookie.substring(i, j) == arg)

            return Cookies.getCookieVal(j);

        i = document.cookie.indexOf(" ", i) + 1;

        if(i == 0)

            break;

    }

    return null;

};

Cookies.clear = function(name) {

  if(Cookies.get(name)){

    var expdate = new Date();

    expdate.setTime(expdate.getTime() - (86400 * 1000 * 1));

    Cookies.set(name, "", expdate);

  }

};

Cookies.getCookieVal = function(offset){

   var endstr = document.cookie.indexOf(";", offset);

   if(endstr == -1){

       endstr = document.cookie.length;

   }

   return unescape(document.cookie.substring(offset, endstr));

};