相关疑难解决方法(0)

使用纯JavaScript(而不是jQuery),有没有一种方法可以测试一个元素是否包含一个类？

目前,我这样做:

HTML:

var test = document.getElementById("test");
var testClass = test.className;

switch (testClass) {
  case "class1":
    test.innerHTML = "I have class1";
    break;
  case "class2":
    test.innerHTML = "I have class2";
    break;
  case "class3":
    test.innerHTML = "I have class3";
    break;
  case "class4":
    test.innerHTML = "I have class4";
    break;
  default:
    test.innerHTML = "";
}

JS:

<div id="test" class="class1"></div>

这导致此输出,这是正确的:

<div id="test" class="class1 class5"></div>

问题是,如果我将HTML更改为此...

var test = document.getElementById("test");
var testClass = test.className;

switch (testClass) {
  case "class1":
    test.innerHTML = "I have …