为什么这个 javascript 计算器不起作用？
我试图用javascript制作这个简单的计算器。我已经检查了类的名称和所有的名称，但我找不到任何问题。除了控制台也没有显示任何问题，但是当我单击按钮时仍然没有任何反应。这是html文件：
<!DOCTYPE html>
<html dir="ltr">
<head>
<meta charset="utf-8">
<meta name="viewport">
<link rel="stylesheet" href="style.css">
<title>Calculator</title>
</head>
<body>
<section class="calculator">
<form>
<div class="previous_op"></div>
<div class="current_op"></div>
</form>
<button class ='clearBtn span-two'>AC</button>
<button class ='delBtn'>DEL</button>
<button class='btn btn-orange' data-num='/'>/</button>
<button class='btn btn-grey' data-num='1'>1</button>
<button class='btn btn-grey' data-num='2'>2</button>
<button class='btn btn-grey' data-num='3'>3</button>
<button class='btn btn-orange' data-num='*'>*</button>
<button class='btn btn-grey' data-num='4'>4</button>
<button class='btn btn-grey' data-num='5'>5</button>
<button class='btn btn-grey' data-num='6'>6</button>
<button class='btn btn-orange' data-num='+'>+</button>
<button class='btn btn-grey' data-num='7'>7</button>
<button class='btn btn-grey' data-num='8'>8</button>
<button class='btn btn-grey' data-num='9'>9</button>
<button class='btn btn-orange' data-num='-'>-</button>
<button class='btn btn-grey' data-num='.'>.</button>
<button class='btn btn-grey' data-num='0'>0</button>
<button class ='span-two equalBtn'>=</button>
</section>
</body>
<script src="javascript.js"></script>
</html>
这是javascript文件：
const btns = document.querySelector('.btn');
const prevOp = document.querySelector('.previous_op');
const currOp = document.querySelector('.current_op');
const equalBtn = document.querySelector('.equalBtn');
const clearBtn = document.querySelector('.clearBtn');
const deleteBtn = document.querySelector('.delBtn');
for (var i = 0; i < btns.length; i++) {
btns[i].addEventListener('click', function() {
let number= btns[i].getAttribute('data-num');
currOp.value += number;
})
}
牛魔王的故事1回答
-
蝴蝶刀刀
你失踪了三个1) 使 querySelector 成为 Nodelist 的 querySelectorAll2) 在 btns[i] 之外写这个3）初始化你的 currOp.valueconst btns = document.querySelectorAll('.btn');const prevOp = document.querySelector('.previous_op');const currOp = document.querySelector('.current_op');const equalBtn = document.querySelector('.equalBtn');const clearBtn = document.querySelector('.clearBtn');const deleteBtn = document.querySelector('.delBtn'); currOp.value="";for (var i = 0; i < btns.length; i++) { btns[i].addEventListener('click', function() { let number= this.getAttribute('data-num'); currOp.value += number; currOp.innerHTML=currOp.value; console.log( currOp.value) })}equalBtn.addEventListener('click', function() { let value = eval(currOp.value); currOp.value = value; currOp.innerHTML=currOp.value; })clearBtn.addEventListener('click', function() { currOp.value = ''; currOp.innerHTML='';})<!DOCTYPE html><html dir="ltr"> <head> <meta charset="utf-8"> <meta name="viewport"> <title>Calculator</title> </head> <body><section class="calculator"> <form> <div class="previous_op"></div> <div class="current_op"></div></form><button class ='clearBtn span-two'>AC</button><button class ='delBtn'>DEL</button><button class='btn btn-orange' data-num='/'>/</button><button class='btn btn-grey' data-num='1'>1</button><button class='btn btn-grey' data-num='2'>2</button><button class='btn btn-grey' data-num='3'>3</button><button class='btn btn-orange' data-num='*'>*</button><button class='btn btn-grey' data-num='4'>4</button><button class='btn btn-grey' data-num='5'>5</button><button class='btn btn-grey' data-num='6'>6</button><button class='btn btn-orange' data-num='+'>+</button><button class='btn btn-grey' data-num='7'>7</button><button class='btn btn-grey' data-num='8'>8</button><button class='btn btn-grey' data-num='9'>9</button><button class='btn btn-orange' data-num='-'>-</button><button class='btn btn-grey' data-num='.'>.</button><button class='btn btn-grey' data-num='0'>0</button><button class ='span-two equalBtn'>=</button></section> </body></html>
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相关分类
JavaScript