<!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>方法1--兼容ie+ff,光标闪烁截断多余文字</title><script type="text/javascript">function ismaxlength(obj){var mlength=obj.getAttribute? parseInt(obj.getAttribute("maxlength")) : ""if (obj.getAttribute && obj.value.length>mlength)obj.value=obj.value.substring(0,mlength)}</script></head><body><textarea maxlength="10" onkeyup="return ismaxlength(this)"></textarea></body></html> <!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>方法2--兼容ie+ff,ctrl复制文字会超出范围.html</title><script language="javascript" type="text/javascript"><!--function imposeMaxLength(Object, MaxLen){return (Object.value.length <MaxLen);}--></script></head><body><textarea name="myName" onkeypress="return imposeMaxLength(this, 10);" ></textarea></body></html> <html><head><title>方法3--无法通过ctrl+c复制（FF无效）</title></head><body><form method=post name=ceshi action="index.htm"> <textarea name=textarea1 onpropertychange=checkMaxLen(this,10,0)></textarea></form> <script language=javascript>var oldValue=new Array();function checkMaxLen(obj,maxlength,num){ if(obj.value.length>maxlength){ obj.value=oldValue[num]; } else{ oldValue[num]=obj.value; }}</script></body></html> <html><head><title>方法4-标闪烁截断多余文字（FF无效）</title><script type="text/javascript">var textarea_maxlen = {isMax : function (){ var textarea = document.getElementByIdx("area"); var max_length = textarea.maxLength;if(textarea.value.length > max_length){ textarea.value = textarea.value.substring(0, max_length); }},disabledRightMouse : function (){document.oncontextmenu = function (){ return false; }},enabledRightMouse : function (){document.oncontextmenu = null;}};</script></head><body><textarea id="area" maxLength="10" onkeyup="textarea_maxlen.isMax()" onfocus="textarea_maxlen.disabledRightMouse()" onblur="textarea_maxlen.enabledRightMouse()" rows="20" cols="100"></textarea></body></html>
