<! 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=gb2312" /> < title > Untitled Document </ title > < SCRIPT language =javascript1.3 > <!--var testleng=300;//允许多少字符串填入function GC_UpdateCharCount() { var desc_el = document.getElementById('desc'); var remainingchars_el = document.getElementById('remainingchars'); var num_remaining = testleng - desc_el.value.length; if (num_remaining >= 0) { remainingchars_el.innerHTML = num_remaining; } else { remainingchars_el.innerHTML = "<font color=red>" + (-num_remaining + '') + " characters over</font>"; }}function isOver(sText) { var intlen=sText.value.length; if (intlen>testleng) { alert("描述特征的内容的字数必修小于或者等于 "+testleng); sText.focus(); sText.select(); } }//--></SCRIPT></head><body><<B>Group description</B><BR><TEXTAREA id=desc onkeydown=GC_UpdateCharCount() onkeyup=GC_UpdateCharCount() onblur="isOver(this);"style="WIDTH: 99%" name=desc rows=4 cols=50></TEXTAREA> <BR>Letters remaining: <SPAN id=remainingchars> <SCRIPT language=javascript1.2><!-- GC_UpdateCharCount(); //--></SCRIPT></SPAN><NOSCRIPT>300 characters allowed </NOSCRIPT></body></html> 效果参考: www.lostfound.cn/CoutChar.html 转载于:https://www.cnblogs.com/xucanzhao/archive/2006/06/08/420594.html