我對JS很新,我試圖做一個簡單的體重計算。它需要用戶的身高和體重進行計算並將其顯示在屏幕上。我已經完成了。現在我的問題是我想在「清除信息」按鈕下顯示結果作爲文本。我想使用DOM來做到這一點。如何寫一個變量undeath邊界
請任何幫助!
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Assignment 4 Starter File</title>
<style>
h1 {text-align: center;}
#calculator
{
width: 600px;
margin: 0px auto;
border: 2px solid #000;
padding: 20px;
}
#values
{
width: 600px;
margin: 50px auto;
pading: 20px;
}
ul {margin-top: 5px;}
</style>
<script>
// code to be called when button is clicked goes here
function calculateResult() {
// this gets the weight
var weight = document.getElementById("weight").value;
//this gets the height
var height = document.getElementById("height").value;
// this calcualtes thet total with a
var calculate = (weight/Math.pow(height,2)) * 703;
//rounds to the 2
var New = calculate.toFixed(2);
New = parseInt(New);
alert(New);
// alert(" your weight is" + weight);
if(calculate <=18){
("your BMI IS: " + calculate);
// alert("your less then 18");
}
}
window.onload = function() {
// reference the button to be clicked
var btnCalculate = document.getElementById("calculate");
// calls the function when the button is clicked
btnCalculate.onclick = calculateResult;
}
</script>
</head>
<body>
<header>
<h1>Body Mass Index (BMI) Calculator</h1>
</header>
<section id="calculator">
<p>
To determine if you're at a healthy weight, enter the following information
and calculate your body mass index (BMI). <span>Enter numbers only please</span>
</p>
<form>
<label for="weight" >Weight (lbs):</label>
<br>
<input type="text" id="weight">
<br>
<br>
<label for="height" >Height (inches):</label>
<br>
<input type="text" id="height">
<br>
<br>
<input type="button" id="calculate" value="Click to Calculate Your BMI"> <br>
<br>
<input type="reset" value="Clear the Information">
<p style="color: red">The total is <span id= "total"> </span></p></p>
</section>
<section id="values">
BMI values are as follows:
<ul>
<li>Below 18: Underweight</li>
<li>Between 18 and 24.9 : Normal</li>
<li>Between 25 and 29.9 : Overweight</li>
<li>Over 30 : Obese</li>
</ul>
</p>
</section>
<script type="text/javascript">
</script>
</body>
</html>
看到這個答案:http://stackoverflow.com/questions/1535268/js-how-to-dynamically-insert-text-into-a-span 基本上,您使用getElementById()檢索範圍並將要顯示的結果分配到其innerHTML字段中。 – Tonkleton 2015-02-23 23:24:55