这道体不难,熟悉基本的api获取对应的节点,更新节点文本内容即可。

// 1. 获取节点
			const zjIncrease = document.getElementById('zjtaishaola');
			const zjDecrease = document.getElementById('zj***ola');

			const klIncrease = document.getElementById('kltaishaola');
			const klDecrease = document.getElementById('kl***ola');

			const totalNd = document.getElementById('total');
			const zjslNd = document.getElementById('zjsl');
			const klslNd = document.getElementById('klsl');

			// 2. 数量和价格
			const zjPrice = 28;
			const klPrice = 5;
			let zjTotal = 0;
			let klTotal = 0;
			let priceTotail = 0;

			// 3. 计算总价
			function computedTotal() {
				totalNd.innerText = zjPrice * zjTotal + klPrice * klTotal;
			}

			// 4. 点击事件
			zjIncrease.onclick = function () {
				zjTotal++;
				zjslNd.innerText = zjTotal;
				computedTotal();
			};

			zjDecrease.onclick = function () {
				zjTotal = --zjTotal >= 0 ? zjTotal : 0;
				zjslNd.innerText = zjTotal;
				computedTotal();
			};

			klIncrease.onclick = function () {
				klTotal++;
				klslNd.innerText = klTotal;
				computedTotal();
			};

			klDecrease.onclick = function () {
				klTotal = --klTotal >= 0 ? klTotal : 0;
				klslNd.innerText = klTotal;
				computedTotal();
			};