使用javascript从文本框中获取价值

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。我想从用户输入的值中计算平均值和总和。该HTML运作良好，但我的JavaScript代码是不知何故。请帮助使用javascript从文本框中获取价值

<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>

来源

2015-12-07 Amher25

你以外什么样的结果您怎么弄？ – unicorn2

尝试在'document.getElementsByName（“english”）'之后添加'[0]''。 –

谢谢，但那不起作用 – Amher25

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>

来源

2015-12-07 07:28:02 Shubham

谢谢！这项工作就像一个魅力。但我不知道“console.log（a）;”是什么？ – Amher25

我只是检查值...我忘了删除它：P – Shubham

哦，我明白了，所以你只需修复getElement的“Name”和“Id”。傻，我，谢谢。 – Amher25

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; 
}

来源

2015-12-07 07:25:44

它不起作用。不过谢谢 – Amher25

对不起。看来你可以解决这个问题，但你也需要删除'form'标签。 –

嘿，我很高兴你找到你的答案，但我想，如果你看到一个不同的，可能帮助你方法：

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，我添加了一个类grade-val在每个元素，如果你只是想添加其他受考虑到你没有修改代码，但只有标记（插入具有相同类的新元素）。就那么简单。

这将在IE8+

来源

2015-12-07 07:49:41

我有固定的工作片段 - 你已经做出了一些错误的存在。现在，它的工作原理

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; 
 
    }

<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>

来源

2015-12-07 07:58:02

使用javascript从文本框中获取价值

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