1、文本框長度限制：
<body >
?<textarea ?onkeypress="return test(this,2)"></textarea>
?<script language="javascript">
??function test(obj,maxlen){????//maxlen為限定的最大長度，超過此長度時寫不進文本框
??? if(obj.value.length>maxlen-1){
??? ?return false;???
??? }???
??}
??</script>
</body>
2、單個中文字符的腳本顯示：
<input type="text" value="aaas測試s"? onfocus="testchinese(this)">
?<script language="javascript">
???function testchinese(obj){
???? var ss = new String(obj.value);
???? alert(ss.length+" "+ss+" "+String.fromCharCode(ss.charCodeAt(4)));
??}
</script>