firefox浏览器不支持innerText的解决方法

<script>
window.onload = function(){
<PRE class=javascript name="code">if(window.navigator.userAgent.toLowerCase().indexOf("msie")==0){ //firefox innerText
HTMLElement.prototype.__defineGetter__( "innerText",
function(){
var anyString = "";
var childS = this.childNodes;
for(var i=0; i<childS.length; i++) {
if(childS[i].nodeType==1)
anyString += childS[i].tagName=="BR" ? '\n' : childS[i].textContent;
else if(childS[i].nodeType==3)
anyString += childS[i].nodeValue;
}
return anyString;
}
);
HTMLElement.prototype.__defineSetter__( "innerText",
function(sText){
this.textContent=sText;
}
);
};</PRE>var test = document.getElementById("test");<BR>
var innerText_s = test.innerText;<BR>
if( innerText_s == undefined ){<BR>
alert( test.textContent ); // firefox<BR>
}else{ <BR>
alert( test.innerText);<BR>
};<BR>
<BR>
<BR>
}<BR>
<BR>
<BR>
</script><BR>
<PRE></PRE>
<P><BR>
</P>
<P>html代码</P>
<P><div id="test"><BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span style="color:red">test1</span> test2<BR>
</div><BR>
</P>