<p>点击按钮切换文本:</p>

​

<p><button onclick="myFunction()">点我</button></p>

​

<div id="myDIV">Hello</div>

function myFunction() {

    var x = document.getElementById("myDIV");

    if (x.innerHTML === "Hello") {

        x.innerHTML = "Swapped text!";

    } else {

        x.innerHTML = "Hello";

    }

}