<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<div id="wrap">
<p id="p">测试</p>
<div id="div1">
<p><span id="span">文字</span></p>
</div>
<div id="div2"></div>
<!--注释-->
<a href="">链接</a>
</div>
</body>
</html>
<script>
var wrap = document.getElementById("wrap");
var div1 = document.getElementById("div1");
var div2 = document.getElementById("div2");
var a = document.getElementById("a");
var p = document.getElementById("p");
var span = document.getElementById("span");
//找子节点个数
function getChild(obj){
var arr=[];
for(var i=0;i<obj.childNodes.length;i++){
if(!(obj.childNodes[i].nodeType==3 && obj.childNodes[i].nodeValue.trim()=="")){
arr.push(obj.childNodes[i]);
}
}
return arr;
}
alert(getChild(wrap).length);
//找第一个子节点
function getFirstChild(obj){
var firstchild=obj.firstChild;
while(firstchild.nodeType==3 && firstchild.nodeValue.trim()==""){
firstchild=firstchild.nextSibling;
}
return firstchild;
}
alert(getFirstChild(wrap).nodeName);
//找最后一个子节点
function getLastChild(obj){
var lastchild=obj.lastChild;
while(lastchild.nodeType==3 && lastchild.nodeValue.trim()==""){
lastchild=lastchild.previousSibling;
}
return lastchild;
}
alert(getLastChild(wrap).nodeName);
</script>
