點(diǎn)擊刪除 控制臺(tái)報(bào)錯(cuò)Cannot read property 'parentNode' of undefined at del

代碼如下

<script type="text/javascript">

window.onload = function() {

var tr = document.getElementsByTagName("tr");

for (var i = 0; i < tr.length; i++) {

tr[i].onmouseover = function() {

this.style.backgroundColor = '#f2f2f2';

}

tr[i].onmouseout = function() {

this.style.backgroundColor = '#fff';

}

}

} //1. 鼠標(biāo)移到不同行上時(shí)背景色改為色值為 #f2f2f2，移開鼠標(biāo)時(shí)則恢復(fù)為原背景色 #fff

var num = 2;

function add() {

num++;

var tr = document.createElement("tr");

var xh = document.createElement("td");

var xm = document.createElement("td");

var del = document.createElement("td");

xh.innerHTML = "xh00" + num;

xm.innerHTML = "<input value='請(qǐng)輸入姓名'/>"; //?

del.innerHTML = "<a href='javascript:del(this)'>刪除</a>";

var table = document.getElementById("table");

table.appendChild(tr);

tr.appendChild(xh);

tr.appendChild(xm);

tr.appendChild(del);

//插入節(jié)點(diǎn)

var tr = document.getElementsByTagName("tr");

for (var i = 0; i < tr.length; i++) {

tr[i].onmouseover = function() {

this.style.backgroundColor = '#f2f2f2';

}

tr[i].onmouseout = function() {

this.style.backgroundColor = '#fff';

}

}

}

function del(obj){

? ? ? ? ? ? var table = obj.parentNode.parentNode.parentNode;

var tr = obj.parentNode.parentNode;

table.removeChild(tr);

? ? ? ? }

</script>

調(diào)用函數(shù)用的<a href="javascript:del(this);">刪除</a>

我的理解是 obj是a標(biāo)簽 obj.parentNode是td

?obj.parentNode.parentNode是tr

obj.parentNode.parentNode.parentNode是table

要?jiǎng)h除table中的tr就是table.removeChild(tr);