脚本说明: 第一步:把如下代码加入<head>区域中 <SCRIPT LANGUAGE="JavaScript"> <!-- Begin maxLen = 130; // max number of characters allowed
function checkMaxInput(form) { if (form.message.value.length > maxLen) // if too long.... trim it! form.message.value = form.message.value.substring(0, maxLen); // otherwise, update 'characters left' counter else form.remLen.value = maxLen - form.message.value.length; } // End --> </script>
第二步:把如下代码加入<body>区域中 <form name=myform action="http://www.csdn.net/javascript/YOUR-SCRIPT.CGI"> <font size="1" face="arial, helvetica, sans-serif"> ( You may enter up to 125 characters. )<br> <textarea name=message wrap=physical cols=28 rows=4 onKeyDown="checkMaxInput(this.form)" onKeyUp="checkMaxInput(this.form)"></textarea> <br> <input readonly type=text name=remLen size=3 maxlength=3 value="130"> characters left</font> </form>
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