Question

我的问题可能存在于保险单选按钮中，并将其值解释为calculate（）函数。我的目标是获取每个选项的价值（紧凑=每天30美元，中级=每天40美元，标准=每天50美元）将这些值乘以租车的天数，并考虑是否是客户购买了给定车辆上的保险（保险=每天+ 15美元，没有保险=每天+0美元）我无法正确编码我需要的功能。

<script type="text/javascript">
   function calculate() {
   var carType = document.getElementById('selectCar').value;
   var days = document.getElementById('daysRenting').value;
   var yInsurance = document.getElementById('yesInsurance');
   var nInsurance = document.getElementById('noInsurance');
   var result = (carType * days * yInsurance * nInsurance);
   totalCost.value= result;
   }
</script>
</head>
<body>
   <div align="center">
      <form name="carForm">
         <p>
            <strong>
         <h1>Car Rental Service</h1></strong></p>
         <hr>
         <select name='selectCar' onchange="calculate(this.value)">
            <option value="0">Pick A Car Type</option>
            <option value="30" id='compact'>Compact</option>
            <option value="40" id='intermediate'>Intermediate</option>
            <option value="50" id='standard'>Standard</option>
         </select>
         <hr>
         <input type="text" id="daysRenting" size="41px" placeholder="How many days are you renting this vehicle?"/>
         <hr>
         I want insurance on this vehicle.<input type="radio" value='15' name='insurance' id="yesInsurance"><br>
         I do not want insurance on this vehicle.<input type="radio" value='0' name='insurance' id="noInsurance">
         <hr>
         <input type="button" onclick="calculate()" value="Click here to process request"><br><br>
         Total Cost to Rent: <input type="number" id='total' name='totalCost' size=8 readonly><br><br>
         <input type="reset" value="Reset"><br>
         <hr>
      </form>
   </div>

Answer 1

你有几个错误：

selectCar

var carType = document.getElementById('selectCar').value;

totalCost未定义（var totalCost = document.getElementById('total');）
var result = (carType * days * yInsurance * nInsurance);中的错误乘法，因为nInsurance和yInsurance是指DOM元素，而不是它们的值，所以它们不能相乘
即使他们提到了值，其中一个总是为零，使result始终为0

这是一个固定版本：

function calculate() {
  var carType = document.getElementById('selectCar').value;
  var days = document.getElementById('daysRenting').value;
  var yInsurance = document.getElementById('yesInsurance');
  var nInsurance = document.getElementById('noInsurance');
  var result = (carType * days);
  if (yInsurance.checked) 
    result += parseInt(yInsurance.value, 10) * days;
  var totalCost = document.getElementById('total');
  totalCost.value = result;
}

<div align="center"><form name="carForm">
<p><strong><h1>Car Rental Service</h1></strong></p><hr>
<select name='selectCar' onchange="calculate(this.value)" id="selectCar">
<option value="0">Pick A Car Type</option>
<option value="30" id='compact'>Compact</option>
<option value="40" id='intermediate'>Intermediate</option>
<option value="50" id='standard'>Standard</option>
</select><hr>
<input type="text" id="daysRenting" size="41px" placeholder="How many days are you renting this vehicle?"/><hr>
I want insurance on this vehicle.<input type="radio" value='15' name='insurance' id="yesInsurance"><br>
I do not want insurance on this vehicle.<input type="radio" value='0' name='insurance' id="noInsurance"><hr>
<input type="button" onclick="calculate()" value="Click here to process request"><br><br>
Total Cost to Rent: <input type="number" id='total' name='totalCost' size=8 readonly><br><br>
<input type="reset" value="Reset"><br><hr>
</form></div>

Answer 2

嗯，首先你没有ID为selectCar的元素 - 你的元素名称不一样。

无法显示选项，收音机和数值输入组合的结果

2 个答案: