使用 javascript 为所有具有另一个类名的元素添加一个 CSS 类
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Use javascript to add a CSS class to all elements with another class name
提问by Hymanncoke
I am trying to use javascript to add a Class to all elements with a different Class. I know you might think this is redundant but for the situation i am in it is needed. i need a way to look though all elements with that class name and add the class but I don't understand how to get a count? I am working with a cms to where I cannot change the styling in the class it self.
我正在尝试使用 javascript 向具有不同类的所有元素添加一个类。我知道您可能认为这是多余的，但对于我所处的情况，这是必要的。我需要一种方法来查看具有该类名的所有元素并添加该类，但我不明白如何计算？我正在使用 cms 到我无法自行更改类中的样式的地方。
$(document).ready(function () {
var ClassBtn = document.getElementsByClassName("buttonSubmit");
ClassBtn.className = ClassBtn.className + " btn";
});
回答by Brandon Boone
Since it appears you are using jQuery:
因为看起来您正在使用jQuery：
$(document).ready(function () {
$('.buttonSubmit').addClass('btn');
});
Without jQuery:
没有 jQuery：
window.onload = function() {
var buttons = document.getElementsByClassName("buttonSubmit"),
len = buttons !== null ? buttons.length : 0,
i = 0;
for(i; i < len; i++) {
buttons[i].className += " btn";
}
}
