js去除范围内所有标签并显示指定字符串

<div id="txt"></div>
<script type="text/javascript">
	function removeLabel(){
		var txt = document.getElementById("txt").innerHTML;
		if(txt==null||txt.length==0){
			setInterval(removeLabel(),500);
		}else{
		document.getElementById("txt").innerHTML=txt.replace(/<.*?>/ig,"").substr(0,100);
		}
	}
	window.addEventListener("load",removeLabel,true);
</script>