jquery读写cookie

jquery cookie需要脚本文件如下:
jQuery.cookie = function(name, value, options) {
if (typeof value != 'undefined') {
   options = options || {};
   if (value === null) {
    value = '';
    options = $.extend({}, options);
    options.expires = -1;
   }
   var expires = '';
   if (options.expires && (typeof options.expires == 'number' || options.expires.toUTCString)) {
    var date;
    if (typeof options.expires == 'number') {
     date = new Date();
     date.setTime(date.getTime() + (options.expires * 24 * 60 * 60 * 1000));
    } else {
     date = options.expires;
    }
    expires = '; expires=' + date.toUTCString();
   }
   var path = options.path ? '; path=' + (options.path) : '';
   var domain = options.domain ? '; domain=' + (options.domain) : '';
   var secure = options.secure ? '; secure' : '';
   document.cookie = [name, '=', encodeURIComponent(value), expires, path, domain, secure].join('');
} else {
   var cookieValue = null;
   if (document.cookie && document.cookie != '') {
    var cookies = document.cookie.split(';');
    for (var i = 0; i < cookies.length; i++) {
     var cookie = jQuery.trim(cookies[i]);
     if (cookie.substring(0, name.length + 1) == (name + '=')) {
      cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
      break;
     }
    }
   }
   return cookieValue;
}
};
页面调用只要引进这个文件
$.cookie("name"); //根据cookie名字取到cookie值
$.cookie("name", "value");//设置cookie 名字,值

$.cookie("name", value, { expires: 7 }); //设置cookie 名字,值,生命周期等属性
$.cookie("name", null); //根据cookie名移除cookie