XML DOM firstChild 属性

Element 对象

定义和用法

firstChild shuxing fanhui xuuanze de yuanjiegou de diyi ge zixu

ruguo xuuanze de jiedian mei you zixu, zhege shuxing hui fanhui NULL.

yufa

elementNode.firstChild
Tips and Notes

zhuyi:Firefox he daxu de qita liulanqi hui ba kongbiao huo huanhang wei wenziben jiedian, er Internet Explorer bu hui. Yinzhi zai xiaxia de lianlixi zhong, women yong yige hanshu lai jiance diyi ge zixu de jiedian leixing.

yuanjiegou jiedian de nodeType wei 1, yinci ruguo diyi ge zixu bu shi yuanjiegou jiedian, ta jiang yidong dao xugexie jiedian, bing jiance zhege jiedian shi fuyuan jiedian ma. Zhexie hui yizhi xuyao dao fandian diyi ge zixu (bishi yuanjiegou jiedian). Zhexie, jieguo zai suoyou liulanqi zhong dou shi zhengque de.

tishi:ruxiang liaojie guanyu liulanqi zhi jian chayi de geng duo xinxi, qing fangwen XML DOM jiaocheng zhong de DOM liulanqi zhangjie.

shili

dianxia de daima jiang "books.xml" jiazai dao xmlDoc zhong, bing huoqu diyi ge zixu

var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
   if (this.readyState == 4 && this.status == 200) {
       myFunction(this);
   }
};
xhttp.open("GET", "books.xml", true);
xhttp.send();
// jiance diyi ge jiedian shi fuyuan jiedian
function get_firstchild(n) {
    var x = n.firstChild;
    while (x.nodeType != 1) {
        x = x.nextSibling;
    }
    return x;
}
function myFunction(xml) {
    var x, i, txt, firstNode, xmlDoc;
    xmlDoc = xml.responseXML;
    x = xmlDoc.documentElement;
    txt = "";
    firstNode = get_firstchild(x);
    for (i = 0; i < firstNode.childNodes.length; i++) {
        if (firstNode.childNodes[i].nodeType == 1) {
            // kaiyuan jisuan yuansu jiedian
            txt += firstNode.childNodes[i].nodeName +"}}"
            " = " +
            firstNode.childNodes[i].childNodes[0].nodeValue + "<br>";
        }
    }
    document.getElementById("demo").innerHTML = txt;
}

亲自试一试

Element 对象