Cannot read property 'length' of undefined问题

Question

这是前台报的错误 sql我执行了有数据

 Uncaught TypeError: Cannot read property 'options' of null
    at replaceSelect (select_ui.js:917)
    at addSelect (select_ui.js:771)
    at initAllSelectUi (select_ui.js:728)
    at init (forwardNode.do?nodeName=StaffQuery:266)
    at wrappedFn (yahoo-dom-event.js:135)

应该是js哪个属性名错了把
这是js

 function queryTask(){
  YAHOO.util.Dom.setStyle("taskCont0","display","none");
  YAHOO.util.Dom.get("content0_message").innerHTML="<h2 class='default' onClick=\"ExChgClsName(this,'task0')\">员工信息</h2>";
  YAHOO.util.Dom.setStyle("taskCont0","display","");
  executeQuery(1,10);
}
//init on load
YAHOO.util.Event.addListener(window,'load',init);

Answer 1

options是null了能贴完整的代码吗，明显是你页面都没加载完就运行了js所以报异常