addEventListener点击

Question

我开始了一些初学者的教程，在这一点上，屏幕应该会在点击按钮后改变数字，但它一直都是0。工作了几个小时。有些小窍门我应该去找错误吗？

​

let buffer = "0";


const screen = document.querySelector(".screen");

document
    .querySelector(".calc-buttons")
    .addEventListener("click", function(event) {
        buttonClick(event.target.innerText);
    });

function buttonClick(value) {
    if (isNaN(parseInt(value))){
        handleSymbol(value);
    } else {
        handleNumber(value);
    }
}


function handleNumber(value){
    
    if (buffer === "0"){
        buffer = value;
    } else {
        buffer += value;
    }
    rerender();
}

function handleSymbol(value){

}

function rerender() {
    screen.innerText = buffer;
}

​

Answer 1

对我来说很好

​

let buffer = "0";


const screen = document.querySelector(".screen");

document
    .querySelector(".calc-buttons")
    .addEventListener("click", function(event) {
        buttonClick(event.target.innerText);
    });

function buttonClick(value) {
    if (isNaN(parseInt(value))){
        handleSymbol(value);
    } else {
        handleNumber(value);
    }
}


function handleNumber(value){
    
    if (buffer === "0"){
        buffer = value;
    } else {
        buffer += value;
    }
    rerender();
}

function handleSymbol(value){

}

function rerender() {
    screen.innerText = buffer;
}

<div class="screen"></div>
<div class="calc-buttons">
  <button>1</button>
  </div>

​