javascript如何动态改变table行属性

 

//得到table对象

var mytable=document.getElementById("onepertable");
//增加方法   

 function add(){
     var tbody = document.createElement("TBODY");
     var row =document.createElement("TR");
     var cell = document.createElement("TD");
     var cell2 = document.createElement("TD");
     var cell3=document.createElement("TD");
     var cell4=document.createElement("TD");
     var cell5=document.createElement("TD");
     cell.innerHTML='';
     cell2.innerHTML='<input name="USER_HM" type="text" class="input0001" size="16" />';
     cell3.innerHTML='<input name="user_address" type="text" class="input0001" size="35" />';
     cell4.innerHTML='<input name="USER_LINKPHONE" type="text" class="input0001" size="16" />';
     row.appendChild(cell);
     row.appendChild(cell2);
     row.appendChild(cell3);
     row.appendChild(cell4);
     tbody.appendChild(row);
     mytable.appendChild(tbody); 
        }

//删除方法
    function removeRow(){  
       var   rowIndex=mytable.rows.length-1 ; 
         if(parseInt(rowIndex)>6){
            mytable.deleteRow(rowIndex)  
          }
      }