Question

这是我的代码。不知道为什么它不工作需要帮助检查我的代码。我正在尝试根据用户输入的值计算平均值和总和。 HTML运行良好，但我的JavaScript代码有点错误。请帮忙

< script >
  function calc() {
    int a = parseInt(document.getElementsByName("english").value);
    int b = parseInt(document.getElementsByName("bmelayu").value);
    int c = parseInt(document.getElementsByName("math").value);
    int d = parseInt(document.getElementsByName("geo").value);
    int e = parseInt(document.getElementsByName("hist").value);

    int sum = a + b + c + d + e;
    int average = (a + b + c + d + e) / 5;

    document.getElementById("sum").innerHTML = sum;
    document.getElementById("average").innerHTML = average;
  } < /script>

<html>

<head>
  <title>Assignment3</title>
</head>
<script>
  function calc() {
    int a = parseInt(document.getElementsByName("english").value);
    int b = parseInt(document.getElementsByName("bmelayu").value);
    int c = parseInt(document.getElementsByName("math").value);
    int d = parseInt(document.getElementsByName("geo").value);
    int e = parseInt(document.getElementsByName("hist").value);

    int sum = a + b + c + d + e;
    int average = (a + b + c + d + e) / 5;

    document.getElementById("sum").innerHTML = sum;
    document.getElementById("average").innerHTML = average;
  }
</script>

<body>
  <form name="form1">
    English :
    <input type="number" name="english">
    <br>Bahasa Melayu :
    <input type="number" name="bmelayu">
    <br>Math :
    <input type="number" name="math">
    <br>Geography :
    <input type="number" name="geo">
    <br>History :
    <input type="number" name="hist">
    <br>
    <button onclick="calc()">Calculate</button>
  </form>
  <p id="sum"></p>
  <p id="average"></p>
</body>

</html>

Answer 1

function calc() {
  var a = parseInt(document.getElementsByName("english")[0].value);
  var b = parseInt(document.getElementsByName("bmelayu")[0].value);
  var c = parseInt(document.getElementsByName("math")[0].value);
  var d = parseInt(document.getElementsByName("geo")[0].value);
  var e = parseInt(document.getElementsByName("hist")[0].value);

  var sum = a + b + c + d + e;
  var average = (a + b + c + d + e) / 5;

  document.getElementById("sum").innerHTML = sum;
  document.getElementById("average").innerHTML = average;
}

Answer 2

  function calc() {
     var a = parseInt(document.getElementById("english").value);
     var b = parseInt(document.getElementById("bmelayu").value);
     var c = parseInt(document.getElementById("math").value);
     var d = parseInt(document.getElementById("geo").value);
     var e = parseInt(document.getElementById("hist").value);
      console.log(a);
    var sum = a + b + c + d + e;
    var average = (a + b + c + d + e) / 5;

    document.getElementById("sum").innerHTML = sum;
    document.getElementById("average").innerHTML = average;
  }

<html>

<head>
  <title>Assignment3</title>
</head>
<body>
    English :
    <input type="number" id="english">
    <br>Bahasa Melayu :
    <input type="number" id="bmelayu">
    <br>Math :
    <input type="number" id="math">
    <br>Geography :
    <input type="number" id="geo">
    <br>History :
    <input type="number" id="hist">
    <br>
    <button onclick="calc();">Calculate</button>
  <p id="sum"></p>
  <p id="average"></p>
</body>

</html>

Answer 3

嘿，我很高兴你找到了答案，但我认为如果你看到不同的方法，它可能对你有所帮助：

function calc() {
  var elements = Array.prototype.slice.call(document.querySelectorAll(".grade-val"));
  var grades = elements.map(function(element) {
    return element.value;
  });

  var sum = grades.reduce(function(s, c) {
    return parseInt(s, 10) + parseInt(c, 10);
  });
  var average = sum / grades.length;

  document.getElementById("sum").innerHTML = sum;
  document.getElementById("average").innerHTML = average;
}

<html>

<head>
  <title>Assignment3</title>
</head>

<body>
  English :
  <input type="number" class="grade-val" name="english">
  <br>Bahasa Melayu :
  <input type="number" class="grade-val" name="bmelayu">
  <br>Math :
  <input type="number" class="grade-val" name="math">
  <br>Geography :
  <input type="number" class="grade-val" name="geo">
  <br>History :
  <input type="number" class="grade-val" name="hist">
  <br>
  <button onclick="calc();">Calculate</button>
  <p id="sum"></p>
  <p id="average"></p>
</body>

</html>

请注意，我在每个元素上添加了一个类grade-val，如果您只是想添加另一个要考虑的主题，则不必修改代码，只需要修改标记（插入）具有相同类的新元素）。就这么简单。

这适用于IE8+

Answer 4

我已经修复了你的代码片段 - 你在那里犯了很多错误。现在它可以工作

＆＃13;

  function calc() {
    var a = parseInt(document.getElementsByName("english")[0].value);
    var b = parseInt(document.getElementsByName("bmelayu")[0].value);
    var c = parseInt(document.getElementsByName("math")[0].value);
    var d = parseInt(document.getElementsByName("geo")[0].value);
    var e = parseInt(document.getElementsByName("hist")[0].value);

    var sum = a + b + c + d + e;
    var average = (a + b + c + d + e) / 5;

    document.getElementById("sum").innerHTML = sum;
    document.getElementById("average").innerHTML = average;
  }

＆＃13;

<html>

<head>
  <title>Assignment3</title>
</head>
<script>
  function calc() {
    int a = parseInt(document.getElementsByName("english")[0].value);
    int b = parseInt(document.getElementsByName("bmelayu")[0].value);
    int c = parseInt(document.getElementsByName("math")[0].value);
    int d = parseInt(document.getElementsByName("geo")[0].value);
    int e = parseInt(document.getElementsByName("hist")[0].value);

    int sum = a + b + c + d + e;
    int average = (a + b + c + d + e) / 5;

    document.getElementById("sum").innerHTML = sum;
    document.getElementById("average").innerHTML = average;
  }
</script>

<body>
  <form name="form1">
    English :
    <input type="number" name="english">
    <br>Bahasa Melayu :
    <input type="number" name="bmelayu">
    <br>Math :
    <input type="number" name="math">
    <br>Geography :
    <input type="number" name="geo">
    <br>History :
    <input type="number" name="hist">
    <br>
    <button onclick="calc()">Calculate</button>
  </form>
  <p id="sum"></p>
  <p id="average"></p>
</body>

</html>

＆＃13;

使用javascript从文本框中获取价值

4 个答案: