看着水了一天的群，终于看到一段高质量的代码了分享一下localStorage

_history : { //缓存isLocalStorage:window.localStorage?true:false,set : function(key,value){ //设置缓存if(this.isLocalStorage){window.localStorage.setItem(key,value);}else{var expireDays = 365; //失效时间var exDate=new Date();exDate.setTime(exDate.getTime()+expireDays*24*60*60*1000);document.cookie=key + "=" + escape(value)+";expires=" + exDate.toGMTString();}},read : function(key){ //读取缓存if(this.isLocalStorage){return window.localStorage.getItem(key);}else{var arr,reg=new RegExp("(^| )"+key+"=([^;]*)(;|$)");if(arr=document.cookie.match(reg)){return unescape(arr[2]);}else{return null;}}},del : function(key){ //删除缓存if(this.isLocalStorage){localStorage.removeItem(key);}else{var exDate = new Date();exDate.setTime(exDate.getTime() - 1);var read_val=this.read(key);if(read_val!=null) document.cookie= key + "="+read_val+";expires="+exDate.toGMTString();}}},

缓存下用户操作 如果用户点击过”往返“我就缓存它 刷新或者下次打开就是往返