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> 
      <span style="color:red">test1</span> test2<BR> 
</div><BR> 
</P>