如何激活某个div

Question

让我们说你的div1和div2的不透明度都是.40。如何在盘旋时仅为div2制作不透明度1.0？

Answer 1

.div1,
.div2 {
  width: 100px;
  height: 100px;
  background: blue;
  opacity: 0.4;
  margin: 10px;
}

.div2:hover {
  opacity: 1;
}

<div class="div1"></div>
<div class="div2"></div>

Answer 2

此处由IrvinDominin在fork上fiddle。最简单的方法是利用不同的类名 - 以这种方式驱动行为。

    var rows = document.getElementsByClassName('demo');
    for (var i = 0; i < rows.length; i++) {
    rows[i].onmouseenter = function (event) {
    for (var j = 0; j < rows.length; j++) {
        if (rows[j] === this) {
            rows[j].className += " other";
        }
    }
};


rows[i].onmouseleave = function (event) {
    var hovers = document.getElementsByClassName('other');
    var len = hovers.length;
    for (var j = 0; j < len; j++) {
        hovers[0].className = hovers[0].className.replace(/\sother(\s|$)/, '');
    }
};

}