表单 获取当前时间

<input type="text" name="shijian" id="shijian" value="" style=" display:none"> 
<script type="text/javascript"> 
window.onload = function(){ 
var nowDate = new Date(); 
var str = nowDate.getFullYear()+"-"+(nowDate.getMonth() + 1)+"-"+nowDate.getDate(); 
document.getElementById("shijian").value=str; 
}
</script>