Question

我试图在每次点击时更改背景颜色。

var button = document.querySelector("button");
var body = document.querySelector("body");
var color = true;

button.addEventListener("click", function(){
    if(color){
        body.style.backgroundColor = "purple";
        color != color;
    }
    else if (!color){
        body.style.backgroundColor = "green";
    }
});

Answer 1

一个小修改。您需要在每次点击时切换变量。您可以通过删除if else并将其替换为else

来进一步简化代码

var button = document.querySelector("button");
var body = document.querySelector("body");
var color = true;

button.addEventListener("click", function() {
  if (color) {
    body.style.backgroundColor = "purple";
  } else {
    body.style.backgroundColor = "green";
  }
  // or equivalent with a ternary operator:
  body.style.backgroundColor = color ? "purple" : "green";

  // color != color is a comparison, but you want an assignment:
  color = !color;
});

<强> Check Fiddle

每次点击都有JavaScript事件（点击）

1 个答案: