用DIV模拟TEXTAREA【QQ空间说说对话框】

<script language="javascript">function show(){	if(document.getElementById("mydiv").innerHTML=="我也说一句"){		document.getElementById("mydiv").innerHTML="";		document.getElementById("mydiv").focus();	}}function hide(){	if(!document.getElementById("mydiv").innerHTML){		document.getElementById("mydiv").innerHTML="我也说一句";	}}</script><div tabindex="0" contenteditable="true" id="mydiv" hidefocus="true" onfocus='show();' onblur='hide();' style="border:1px solid #ccc;width:200px;height:200px;">我也说一句</div>