Question

请帮我调试我的代码：

<!DOCTYPE HTML>
<html lang="en-us">
<head>
  <meta charset="utf-8">
  <title> Miles to Kilometers Conveter</title>
  <script type="text/javascript">
/* Defining Table: Program to convert miles to kilometers.
 * Input: Miles
 * Processing: How many kilometers in a amount of miles inputed
 * Output: output total kilometers
 */
     function milesToKilo(){
         var miles= getElementByID=("milesinput");
         var kilo=1.60934;
         var k= parseFloat(kilo);
         var total= miles*k;
        document.getElementById('outputDiv').innerHTML = total;
    }
  </script>
</head>

<body>
  <h2>Miles to Kilometers Converter</h2>
  How many Miles?<input type="text" id="milesinput">
  <button type="button" onclick="milesToKilo()">Convert</button>
  <div id='outputDiv'></div>
</body>
</html>

Answer 1

这是一个解决方案，您需要获取元素的值并从中解析一个int。

http://plnkr.co/edit/NOYYKx0bYqJ2QJ21prUc?p=preview

function milesToKilo(){ 
  var miles = parseInt(document.getElementById("milesinput").value); 
  var kilo =1.60934; 
  var k = parseFloat(kilo); 
  var total= miles*k; 
  document.getElementById('outputDiv').innerHTML = total; 
}

Answer 2

In [24]: A Out[24]: array([[4, 5, 1], [8, 0, 1]]) In [25]: B Out[25]: array([[4, 1, 1], [8, 0, 1]]) In [26]: np.where(A == B,A,0) Out[26]: array([[4, 0, 1], [8, 0, 1]]) In [27]: A*(A==B) Out[27]: array([[4, 0, 1], [8, 0, 1]])应为var miles = getElementById=("milesinput")：请注意var miles = getElementById("milesinput")和=之间缺少getElementById。除此之外......

(被分配了miles的值，这是一个HTML getElementById("milesinput") - 这是变量JavaScript的特定种，而不是element。

此类型的number具有element属性。您可以使用value访问它，但它是miles.value类型。您需要将其转换为如此数字：

string

调试帮助（继续显示NaN）

2 个答案: