<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<script src="jquery.js" type="text/javascript"></script>
</head>
<body>
<textarea name="s1" id="test" rows="5" cols="50" maxlength="10" id="test"></textarea>
<br>共可输入10字符，还剩 <span id="testtest"></span>个字符</font>
</body>
</html>
<script type="text/javascript">
$(function(){
$("#testtest").html(10);
document.getElementById("test").onpropertychange =document.getElementById("test").onkeyup= function(){
var lenE = this.value.length;
var tno = document.getElementById("testtest");
tno.innerHTML = 10 - lenE ;
if (tno.innerHTML < 0) {
var tmp = 0 ;
var cut = this.value.substring(0, 10);
for (var i=0; i<cut.length; i++){
tmp += /[\u4E00-\u9FA5\uF900-\uFA2D]/.test(cut.charAt(i)) ? 2 : 1;
if (tmp > 10) break;
}
this.value = cut.substring(0, 10);
}
}
})
</script>