text: function preloader(){
      if (document.images){
          var img1 = new Image();
          img1.src = "../img/bg/bg_welcome.jpg";
      }
  }
  
  function addLoadEvent(func) {
      var oldonload = window.onload;
      if(typeof window.onload != 'function'){
          window.onload = func;
      }else{
          window.onload = function(){
              if(oldonload){
                  oldonload();
              }
              func();
          }
      }
  }
  addLoadEvent(preloader);
  
  function go(str){
  	switch (str) {
  	case "zhaohuan":
  		str = "../lottery/lottery.html";
  		break;
  	case "jinji":
  		str = "/lottery/myCard.html";
  		break;
  	case "huodong":
  		str = "/huodong/huodongPage.html";
  		break;
  	case "rank":
  		str = "/user/rankPage.html?orderParam='rmb'";
  		break;
  	}
  	window.location.href = str;
  }