userData && sessionStorage

  <script>
  //userData类
  var RuserData={
   o:null,
   timeExpires:7,
   browser:'',
   //初始化userdata
   init:function()
   {
    if(this.browser != '')
     return true;
    if(window.ActiveXObject)//for IE
    {
     try
     {
      this.o=document.createElement("input");
      this.o.id="Ruserdata";
      this.o.type="hidden";
      this.o.style.behavior="url(#default#userData)";
      this.browser='ie';
      document.body.appendChild(this.o);
      return true;
     }
     catch(e){return false;}
    }
    else if(window.sessionStorage)//FF 2.0+
    {  
     try
     {
      this.o=window.sessionStorage;
      this.browser='ff';
      return true;
     }
     catch(e){return false;}
    }
    return false;
   },
   setVal:function(key,val,timeout/*正定义超时时间,为空用默认值*/)
   {
    this.init();
    if(this.browser == 'ie')
    {
     try{
      this.o.load(key);
      this.o.expires=typeof timeout == 'undefined' ? this.getTimeLimit(this.timeExpires) : this.getTimeLimit(timeout);
      this.o.setAttribute('value',val);
      this.o.save(key);
      return true;
     }
     catch(e){return false}
     
    }
    else if(this.browser == 'ff')
    {
     try{this.o.setItem(key,val);return true;}
     catch(e){return false}
    }
   },
   getVal:function(key)
   {
    this.init();
    if(this.browser == 'ie')
    {
     try{
      this.o.load(key);
      return this.o.getAttribute('value');
     }
     catch(e){return false;}    
    }
    else if(this.browser == 'ff')
    {
     try{return this.o.getItem(key);}
     catch(e){return false}
    }   
   },
   delVal:function(key)
   {
    this.init();
    if(this.browser == 'ie')
    {
     try{
      this.o.load(key);
      this.o.expires=new Date(315532799000).toUTCString();
      this.o.save(key);
      return true;
     }
     catch(e){return false;}    
    }
    else if(this.browser == 'ff')
    {
     try{this.o.removeItem(key);return true;}
     catch(e){return false}
    }
   },
   getTimeLimit:function(days/*设置超时天数*/)
   {
    var d=new Date();
    d.setDate(d.getDate() + days);
    return d.toUTCString();
   }
  };

 

  window.onload=function()
  {
   //alert(RuserData.delVal('renchao'));
   //alert(RuserData.setVal('renchao','我是中国人'));
   alert(RuserData.getVal('renchao'));

 

  }
  </script>