Javascript 点击更改背景颜色和计数点击

Question

I have a problem. I have code as below:

const btnHappyOne = document.getElementById("happy-btn-1");
const btnHappyTwo = document.getElementById("happy-btn-2");
const btnHappyThree = document.getElementById("happy-btn-3");

function changeHappyBgColor(e){
    let happyColor = e.target.style.backgroundColor;
    if (happyColor != "red") {
        e.target.style.backgroundColor = "red";     
    }
    else {

        e.target.style.backgroundColor = "";
        
    }
}

btnHappyOne.addEventListener('click', changeHappyBgColor);
btnHappyTwo.addEventListener('click', changeHappyBgColor);
btnHappyThree.addEventListener('click', changeHappyBgColor);

This code change color of button when I click. My problem is that I want add some codes to count number of button whenever it change to red. When I click to change background color to none, the number of button also degrease. Thank you.

Answer 1

Add var number=0; below consts, in if block use number++ ; and in else block use number-- ; You can track it in console to see the value, console.log(number); I hope this is what are you asking for