动态新增文本框

<html>
   <head>
     <meta http-equiv="Content-Type" content="text/html; charset=GB2312">
     <script>
       var count = 0;

       function addByScript() {
         var table = document.getElementById("tbl1");
         var newRow = table.insertRow(table.rows.length);
         newRow.id = "row" + count;

         var contentCell = newRow.insertCell(-1);
         contentCell.innerHTML = '<input type="text" />';
         contentCell = newRow.insertCell(-1);

         var delBtn = document.createElement("input");
         delBtn.type = "button";
         delBtn.className = "button";
         delBtn.id = "btnDel"+count;
         delBtn.value = "删除";
         delBtn.onclick = new Function("del(this)");
         contentCell.appendChild(delBtn);

         count++;
       }

       function del(obj) {
         var row = obj.parentNode.parentNode;
         row.parentNode.removeChild(row);
       }
     </script>
   </head>
   <body>
     <fieldset>
<legend>
         insertRow新增
</legend>
       <input type="button" class="button" value="新增" onclick="addByScript()"/>
       <table id="tbl1">
       </table>
     </fieldset>
   </body>
</html>