网站建设是指使用标识语言（markup language)，通过一系列设计、建模、和执行的过程将电子格式的信息通过互联网传输，最终以图形用户界面（GUI）的形式被用户所浏览。简单来说，网页设计的目的就是产生网站。简单的信息如文字，图片（GIF，JPEG，PNG）和表格，都可以通过使超文件标示语言、可扩展超文本标记语言等标示语言放置到网站页面上。
大多数文本编辑软件都有显示行号的功能，你是不是想让网页里的文本输入框也有这样的行号显示呢？那请你看一下Windy2000编写的这个效果吧：
<HTML><HEAD><TITLE>DirMap</TITLE><meta http-equiv='Content-Type' content='text/html; charset=gb2312'></HEAD><style>* { font-size: 12px}body { margin: 10px; padding: 0px}A { COLOR: black; TEXT-DECORATION: none;}A:hover { COLOR: black; TEXT-DECORATION: none;}A:link { TEXT-DECORATION: none}A:visited { TEXT-DECORATION: none}table.list{ cursor: default; border:1px solid #cccccc background-color: #cccccc; border-collapse: collapse; border-Color: #cccccc;}</style><script>function check_form() { var the_form = document.forms[0]; if(!/^[\w\.]+$/.test(the_form.name.value)) { alert('Bad File Name !'); the_form.name.focus(); return false; } if(!/^[0-7]{3}$/.test(the_form.attrib.value)) { alert('Bad File Attrib !'); the_form.attrib.focus(); return false; } if(the_form.del.checked) { return confirm('Are you sure to delete the file ?'); } return true;}function show_ln(){ var txt_ln = document.getElementById('txt_ln'); var txt_main = document.getElementById('txt_main'); txt_ln.scrollTop = txt_main.scrollTop; while(txt_ln.scrollTop != txt_main.scrollTop) { txt_ln.value += (i++) + '\n'; txt_ln.scrollTop = txt_main.scrollTop; } return;}function editTab(){ var code, sel, tmp, r var tabs='' event.returnValue = false sel =event.srcElement.document.selection.createRange() r = event.srcElement.createTextRange() switch (event.keyCode){ case (8) : if (!(sel.getClientRects().length > 1)){ event.returnValue = true return } code = sel.text tmp = sel.duplicate() tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) sel.setEndPoint('startToStart', tmp) sel.text = sel.text.replace(/^\t/gm, '') code = code.replace(/^\t/gm, '').replace(/\r\n/g, '\r') r.findText(code) r.select() break case (9) : if (sel.getClientRects().length > 1){ code = sel.text tmp = sel.duplicate() tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) sel.setEndPoint('startToStart', tmp) sel.text = '\t'+sel.text.replace(/\r\n/g, '\r\t') code = code.replace(/\r\n/g, '\r\t') r.findText(code) r.select() }else{ sel.text = '\t' sel.select() } break case (13) : tmp = sel.duplicate() tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) tmp.setEndPoint('endToEnd', sel) for (var i=0; tmp.text.match(/^[\t]+/g) && i<tmp.text.match(/^[\t]+/g)[0].length; i++) tabs += '\t' sel.text = '\r\n'+tabs sel.select() break default : event.returnValue = true break }}</script><BODY><div style='font-weight:bold; font-size: 18px'>File: ../fso/upload_manager.class.php</div><br><table width='700' class='list' border='1' bgcolor='#eeeeee' bordercolorlight='#000000' bordercolordark='#FFFFFF' cellpadding='0' cellspacing='0'> <tr bgcolor='#cccccc'> <td colspan='2' height='20'> <div align='center'><b>File Information</b> </div> </td> </tr> <tr> <td colspan='2'> <br /> <form name='edit' method='post' action='fso_edit.php' onsubmit='return check_form()'> <table width='90%' border='0' align='center' > <tr> <td>Name ：</td> <td><input type='text' name='name' value='upload_manager.class.php'></td> </tr> <tr> <td valign='top'>Time ：</td> <td>2003-10-02 00:55:59</td> </tr> <tr> <td>Attrib ：</td> <td><input type='text' name='attrib' value='666'> (rw-rw-rw-)</td> </tr> <tr> <td>MoveTo ：</td> <td> <select name='move'> <option value=''>NoMove</option> <option value='../fso/../'>Parent Direction</option> </select> </td> </tr> <tr> <td>Size ：</td> <td>6.2 KB</td> </tr> <tr> <td valign='top'>Content ：</td> <td> <textarea id='txt_ln' name='content' rows='10' cols='4' style='overflow:hidden;height:200px;border-right:0px;text-align:right' readonly></textarea><textarea id='txt_main' name='content' rows='10' cols='70 'onkeydown='editTab()' onchange="document.forms[0].modi.value='ture'" onscroll='show_ln()' wrap='off' style='overflow:auto;height:200px;padding-left:5px;border-left:0px'>/********************************************* ** Name : Upload Manager ** Author : Windy_sk ** Time : 2003-05-10 ** Email : flyhorses@sina.com ** HomePage: None (Maybe Soon) ** Notice : U Can Use & Modify it freely, ** BUT PLEASE HOLD THIS ITEM. ** *********************************************/class Upload_Manager { var $upload_path = ""; var $upload_counter = 0; var $upload_result = array(); var $upload_rename = false;function Upload_Manager($upload_path = 'upload/', $upload_rename = false, $relative = false) {}}</textarea> <script>for(var i=1; i<=20; i++) document.getElementById('txt_ln').value += i + '\n';</script> <input type='hidden' name='modi' value=''> </td> </tr> <tr> <td colspan='2'> <div align='center'><br> <input type='hidden' name='name_org' value='upload_manager.class.php'> <input type='hidden' name='path' value='../fso'> <input type='Submit' value=' 确 定 ' name='Submit'> <input type='reset' value=' 重 置 ' name='reset'> <input type='checkbox' value='true' name='del'> 删 除 </div> </td> </tr> </table> </form> </td> </tr></table></BODY></HTML>
[Ctrl+A 全部选择 提示：你可先修改部分代码，再按运行]
（出处：蓝色理想）大多数人在上网的时候，都会浏览网页提供给我们的信息。
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