JS工厂模式实战：解决Token存储与跨域请求兼容

/**
  * Storage Factory -Author 吴双 cnblogs.com/tdws
  */
 StorageUtilManager: new Object({
  createStorageUtil: function () {
   if (window.applicationCache) {
    return AppUtil.LocalStorageUtil;
   } else {
    return AppUtil.CookieStorageUtil;
   }
  }
 }),
 /**
  * implement Storage -Author 吴双
  * write()
  * get()
  */
 CookieStorageUtil: {
  write: function (key, dataObj) {
   this._clearCookie(key);
   //写入的字符串
   var dataObjStr = JSON.stringify(dataObj);
   this._setCookie(key, dataObjStr, 15);
  },
  get: function (key) {
   return this._getCookie(key);
  },
  _setCookie: function (cname, cvalue, exdays) {
   var d = new Date();
   d.setTime(d.getTime() + (exdays * 24 * 60 * 60 * 1000));
   var expires = "expires=" + d.toUTCString();
   var path = "path=/";
   document.cookie = cname + "=" + cvalue + "; " + expires + "; " + path;
  },
  _getCookie: function (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 null;
  },
  _clearCookie: function (key) {
   this._setCookie(key, "", -1);
  }
 },
 /**
  * implement Storage cnblogs.com/tdws
  * write()
  * get()
  */
 LocalStorageUtil: {
  write: function (key, dataObj) {
   this._writeLocalStorage(key, dataObj);
  },
  get: function (key) {
   return this._getFromLocalStorage(key);
  },
  _writeLocalStorage: function (key, dataObj) {
   var localStorage = window.localStorage;
   localStorage.removeItem(key);
   //对象转化为字符串,将objStr按正常的方式存入localStorage中
   var dataObjStr = JSON.stringify(dataObj);
   localStorage.setItem(key, dataObjStr);
  },
  _getFromLocalStorage: function (key) {
   var localStorage = window.localStorage;
   return localStorage.getItem(key);
  },
  _removeLocalStorage: function (key) {
   var localStorage = window.localStorage;
   localStorage.removeItem(key);
  }
 }