js div的显示与隐藏

<div title="当前活动" id="workItem" href="../TiPLM/Process/FrmWork.aspx?type=WorkItem"></div>     
<div title="未来任务" id="FutureTask" href="../TiPLM/Process/FrmWork.aspx?type=FutureTask" style="display:none"></div>
<div title="已完成活动" id="FinishIns" href="../TiPLM/Process/FrmWork.aspx?type=FinishIns"  style="display:none"></div>   

div设置style为none的时候，div是不显示的

之后如果需要显示则对style设置为block

document.getElementById('FutureTask').style.display="block";