Question

第二段函数页面加载的时候不显示求前辈指导一下

function showPic(whichpic){
var source=whichpic.getAttribute("href");
var thdx=document.getElementById("kong");
thdx.setAttribute("src",source);
}

function countBodyChildren(){
var body_element=document.getElementByTagName("body")[0];
alert(body_element.childNodes.length);
}
window.onload=countBodyChildren;

Answer 1

function countBodyChildren(){
        var body_element=document.getElementsByTagName("body")[0];
        alert(body_element.childNodes.length);
}
window.onload=countBodyChildren;

getElementsByTagName   是Elements 加s，复数