
以下是该效果的源码:
<html> <head> <meta http-equiv="Content-Type" content="text/html;charset=utf-8"> <title>显示行号的文本框效果,兼容ie、火狐等浏览器</title> <style type="text/css"> #main{color:#666} textarea{border:1px solid #7f9db9;font-size:9pt;width:430px;color:#000} .grey{color:#999} #msg1,#msg2,#msg3,#msg4{ display:none} #ol{position:absolute;z-index:1;padding:0px;margin:0px;border:0px;background:#ecf0f5;width:23px;text-align:left; } #li{background:#ecf0f5;height:160px;overflow:hidden;width:32px;border-right:0;line-height:20px;margin:0px;padding:0px;text-align:center} #c2{font-family:Arial, Helvetica, sans-serif;height:160px; margin:0px; width:416px;padding:0 0 0 35px;overflow-x: hidden;line-height:20px;} </style> <script type="text/javascript"> String.prototype.trim2=function(){ return this.replace(/(^s*)|(s*$)/g, ""); } function F(objid){ return document.getElementById(objid).value; } function G(objid){ return document.getElementById(objid); } </script> </head> <body onLoad="keyUp();"> <div> <table width="100%" border="0" cellspacing="0" cellpadding="0" style="position:relative"><tr> <td width="55%"> <div id="ol"><textarea cols="2" rows="10" id="li" disabled></textarea></div> <textarea name="co" cols="60" rows="10" wrap="off" id="c2" onblur="check("2")" onKeyUp="keyUp()" onFocus="clearValue("2")" onscroll="G("li").scrollTop=this.scrollTop;" oncontextmenu="return false" class="grey">请在这里粘入多段字看一看。 </textarea> </td> </tr> </table> </div> <em class="block" id="msg2">文本框没有内容。</em> <script type="text/javascript"> var msgA=["msg1","msg2","msg3","msg4"]; var c=["c1","c2","c3","c4"]; var slen=[50,20000,20000,60];//允许最大字数 var num="";var isfirst=[0,0,0,0,0,0]; function isEmpty(strVal){if( strVal=="" )return true;elsereturn false; } function isBlank(testVal){var regVal=/^s*$/; return (regVal.test(testVal)) } function chLen(strVal){strValstrVal=strVal.trim2();var cArr=strVal.match(/[^x00-xff]/ig); return strVal.length+(cArr==null ? 0 : cArr.length);} function check(i){var iValue=F("c"+i);var iObj=G("msg"+i);var n=(chLen(iValue)>slen[i-1]);if((isBlank(iValue)==true)||(isEmpty(iValue)==true)||n==true){ iObj.style.display ="block";}else{ iObj.style.display ="none";} } function checkAll(){for(var i=0;i<msgA.length;i++){check(i+1);if(G(msgA[i]).style.display=="none"){ continue;}else{ alert("填写错误,请查看提示信息!"); return;}}G("form1").submit(); } function clearValue(i){G(c[i-1]).style.color="#000";keyUp();if(isfirst[i]==0){G(c[i-1]).value="";}isfirst[i]=1; } function keyUp(){var obj=G("c2");var str=obj.value;strstr=str.replace(/
/gi,"");strstr=str.split("
");n=str.length;line(n); } function line(n){var lineobj=G("li");for(var i=1;i<=n;i++){if(document.all){ num+=i+"
";}else{ num+=i+"
";}}lineobj.value=num;num=""; } function autoScroll(){var nV=0;if(!document.all){nV=G("c2").scrollTop;G("li").scrollTop=nV;setTimeout("autoScroll()",20);} } if(!document.all){ window.addEventListener("load",autoScroll,false); } </script> </body> </html> 以上就是javascript如何实现行号显示的文本框效果的源代码,希望对大家的学习有所帮助。