单击“预览”按钮，显示textarea中html代码对应的web页面

Question

<SCRIPT language=JavaScript>
function a()
{
var c=document.all.x.value
document.all.m.innerHTML=c.replace(/\n/g,"<br>").replace(/ /g,"&nbsp;")
}
</SCRIPT>
<textarea rows=6 cols=60 id=x></textarea>
<input  type=button value=privew onclick='a()'>
<br>
<div id=m></div>

Answer 1

<form name="aa">
<textarea rows="17" name="bb" cols="44"></textarea>
<input type="button" value="预览" name="B1" onclick="nw=window.open('about:blank','nn','width=400,height=200');nw.document.write(aa.bb.value)"></p>
</form>