计算机作业,麻烦老师检查
来源：4-14 项目作业
慕尼黑8359237
2021-09-09 14:26:49
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<input type='text' id='num1' />
<select id='operate'>
<option value='+'>+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
</select>
<input type='text' id='num2' />
<input type='button' value=' = ' id="btn" />
<input type='text' id='result' />
<script>
// 获取所有有id的元素
var num1 = document.getElementById('num1');
var operate = document.getElementById('operate');
var num2 = document.getElementById('num2');
var btn = document.getElementById('btn');
var result = document.getElementById('result');
//给=号框点击事件
btn.onclick = function(){
// 获取num1,num2,和operate的值,进行运算后把值赋给result框
var num1Value = Number(num1.value);
var num2Value = Number(num2.value);
var resultNum;
switch(operate.value){
case '+':
resultNum = num1Value + num2Value;
break;
case '-':
resultNum = num1Value - num2Value;
break;
case '*':
resultNum = num1Value * num2Value;
break;
case '/':
resultNum = num1Value / num2Value;
break;
};
result.value = resultNum;
};
</script>
</body>
</html>
1回答
-
好帮手慕慕子
2021-09-09
同学你好，代码实现是对的，很棒！！！祝学习愉快~
0
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