报错： Uncaught TypeError: Cannot set property 'onmousedown' of undefined
function getByClass(clsName,parent){
var oParent=parent?document.getElementById(parent):document,
eles=[],
elements=oParent.getElementsByTagName('*'); //获取所有元素
for(var i=0,l=elements.length;i<l;i++){ //可以同时初始化多个变量
if(elements[i].clsName==clsName){
eles.push(elements[i]);
}
}
return eles;
}
window.onload=drag;
function drag(){
var otitle=getByClass('login_logo_webqq','loginPanel')[0];
otitle.onmousedown=funDown; //当鼠标按下的时候调用函数funDown
}
function funDown(){
document.onmousemove=function(event){
event=event || window.event;
document.title=event.clientX+','+event.clientY;
}
}
