javascript - 遍历 JavaScript "getElementsByTagName()"对象

Question

如何正确地循环遍历从选择器上的“getElementsByTagName()”返回的对象。我好像没弄对。

例如，如果我有一堆这样的 div:

<div class="wrapper">
<div class="test1">this is a div</div>
<div class="test2">this is a div</div>
<div class="test1">this is a div</div>
<div class="test2">this is a div</div>
<div class="test1">this is a div</div>
<div class="test2">this is a div</div>
</div>

我想像这样遍历“getElementsByTagName()”的结果:

var wrapper = document.querySelector(".wrapper");

var divs = wrapper.getElementsByTagName("div");

for (i = 0; i < divs.length; ++i) {
   each = divs[i];
   if (each.classList.contains("test2")) {
    this.style.display = "none";
   }
}

这是一个 fiddle :http://jsfiddle.net/Y2Yzv/1/

Answer 1

控制台出现错误:Uncaught TypeError: Cannot set property 'display' of undefined

尝试:

var wrapper = document.querySelector(".wrapper");

var divs = wrapper.getElementsByTagName("div");

for (i = 0; i < divs.length; ++i) {
   each = divs[i];
   if (each.classList.contains("test2")) {
    each.style.display = "none";
   }
}

Demo