javascript 判断输入的文本的中文字数或者英文单词数目，混输一样判断

javascript  判断输入的文本的中文字数或者英文单词数目，混输一样判断
看代码

 <script>
function testreg(){
 var s = document.frm.aa.value;
 var s1 = s.replace(/([^/x00-/xff])/g,' $1 ');
 var s2 = s1.replace(//s+/ig,' ');
 var s2 = s2.replace(/^ */,'').replace(/ *$/,'');
 var len = s2.split(' ').length;
 alert(s2 + '/r/n字数：' + len);
}
</script>

<form id="frm" name="frm" action="t.html" method="post">
<textarea id="aa" name="aa" cols="65" rows="5">I过am a 有 you as
I过am a 有 you as
</textarea>
<input type="button" id="btn" name="btn" value="test" onclick="testreg()"/>
</form>