29 lines
606 B
JavaScript
29 lines
606 B
JavaScript
let count = 0;
|
|
|
|
// 任务：
|
|
// 1. 获取数字元素和 3 个按钮
|
|
// 2. 点击按钮时更新 count
|
|
// 3. 每次修改后，把最新 count 渲染到页面
|
|
const num = document.getElementById("value")
|
|
const del = document.getElementById("decrease-btn")
|
|
const add = document.getElementById("increase-btn")
|
|
const reset = document.getElementById("reset-btn")
|
|
|
|
function ren() {
|
|
num.textContent = count
|
|
}
|
|
|
|
add.addEventListener("click", function () {
|
|
count++
|
|
ren()
|
|
})
|
|
|
|
del.addEventListener("click", function () {
|
|
count--
|
|
ren()
|
|
})
|
|
|
|
reset.addEventListener("click", function () {
|
|
count = 0
|
|
ren()
|
|
}) |