<HTML>
<HEAD>
<TITLE> New Document </TITLE>
</HEAD>
<BODY>
<FORM METHOD=POST ACTION="" name=form1>
<TEXTAREA NAME="txt1" ROWS="6" COLS="40" onkeydown="return check_frm()" onpaste="return false" oncopy="return false;" oncut="return false;"></TEXTAREA>
<INPUT TYPE="button" name="button1" value="button1">
</FORM>
</BODY>
</HTML>
<SCRIPT LANGUAGE="vbScript">
<!--
'求字符串的绝对字节数(汉字为两个字节)
function my_len(str)
dim count,i
count=0
if str<>"" then
for i=1 to len(str)
if asc(mid(str,i,1))<0 then
count=count+2
else
count=count+1
end if
next
end if
my_len=count
end function
function check_frm()
if my_len(form1.txt1.value)>10 then
check_frm=false
end if
end function
//-->
</SCRIPT>