document.write("<br />今天日期为"+(today.getMonth()+1)+"/"+today.getDate()+"/"+today.getYear()+"<br />");

------解决方案--------------------
HTML code

<script>
var today=new Date();
document.write("<br />今天日期为"+(today.getMonth()+1)+"/"+today.getDate()+"/"+today.getYear()+"<br />");
</script>

------解决方案--------------------
var today=new Date();
		document.write(" <br> 今天日期位；",today.getMonth()+1+"/",today.getDate(),"/",today.getYear()+" <br> ");

------解决方案--------------------
<script>
var today=new Date();
document.write("<br />今天日期为"+(today.getMonth()+1)+"/"+today.getDate()+"/"+today.getYear()+"<br />");
</script>
你可以看浏览器的左下角,如果有个感叹号的话你双击就能看见错误信息了.