为什么只有第一个节点对象会变，这是怎么回事？？？

Question

function navTopMouseOver(navDivId, navTopAClass, navTopAOverClass){
var collTopANodes = document.getElementById(navDivId).getElementsByTagName("a");
for (var x = 0; x < collTopANodes.length; x++) {
collTopANodes[x].onmouseover = function(){
collTopANodes[x].className = navTopAOverClass;
}();
}
}
我想实现在节点对象上鼠标进入就改变class，但是这段代码在网页一加载，我还没有让鼠标经过，它的class就变了，而且不循环，只有第一个节点对象会变，这是怎么回事？

Answer 1

collTopANodes[x].onmouseover = function(){collTopANodes[x].className = navTopAOverClass;}();把最后那个括号删掉collTopANodes[x].onmouseover = function(){collTopANodes[x].className = navTopAOverClass;};

Answer 2

当 onmouseover 被调用时 for 已经循环结束，你代码中并没有匿名函数，() 只是自动执行把 for 循环改为下面这样for&nbsp;(var&nbsp;x = 0; x < collTopANodes.length; x++) {&nbsp;&nbsp;&nbsp;&nbsp;(function(a) {&nbsp;// 开始匿名函数，a 为 x 的参考&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;collTopANodes[a].onmouseover =&nbsp;function(){&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;this.className = navTopAOverClass;&nbsp;&nbsp;&nbsp;&nbsp;})(x);&nbsp;// 将 x 传入匿名函数}