如何利用js删除指定行
<input name= "l1 " type= "button " id= "l1 " onClick= "add(tab); " value= "增加一段 " >
<table width= "540 " border= "1 " id= "tab ">
<td width= "122 " align= "center "> 长度 </td>
<td width= "90 " align= "center "> 显示内容 </td>
<td width= "54 " align= "center "> 颜色 </td>
<td width= "36 " align= "center "> 操作 </td>
</table>


<SCRIPT LANGUAGE= "JavaScript ">
var i=0;
function add(obj)
{var newrow=tabnum.insertRow();
var newcell=newrow.insertCell(0);
newcell.innerHTML= " <td width=122> <center> 第 "+(i+1)+ "段长度 </center> </td> ";

newcell=newrow.insertCell(1);
newcell.innerHTML= ".... ";

newcell=newrow.insertCell(2);
newcell.innerHTML= ".... ";

newcell=newrow.insertCell(3);
newcell.innerHTML= " <td align= 'center '> <input name= 'del ' type= 'button ' id= 'del ' onClick= 'delRow(this.parentElement.parentElement,i) ' value= '删除 '> </td> ";
i++;
}
function delRow(src, rowIndex)
{
src.parentElement.deleteRow(rowIndex);
i--;
}
</script>
为什么每次只是删除最后一行，而不是指定的那一行呢？

[解决办法]

改成这样就可以了
newcell.innerHTML= " <td align= 'center '> <input name= 'del ' type= 'button ' id= 'del ' onClick= 'delRow(this.parentElement.parentElement, "+i+ ") ' value= '删除 '> </td> ";
主要是你传进的i为变量。