我正在尝试创建一个基本的 HTML/JavaScript BMI 计算器。
下面应该显示一条消息:您的体重指数是:，然后下面的消息是这意味着您是: 根据上面计算的 BMI。
请有人帮我修复我的计算器，我知道我的 if 语句有问题？谢谢。
Less than 18.5 Underweight
18.5 to 25 Normal
25-30 Overweight
More than 30 Obese
.
<html>
<head>
<title>BMI Calculator</title>
<script type="text/javascript">
function computeBMI()
{
//Obtain user inputs
var height=Number(document.getElementById("height").value);
var heightunits=document.getElementById("heightunits").value;
var weight=Number(document.getElementById("weight").value);
var weightunits=document.getElementById("weightunits").value;
//Convert all units to metric
if (heightunits=="inches") height/=39.3700787;
if (weightunits=="lb") weight/=2.20462;
//Perform calculation
var BMI=weight/Math.pow(height,2);
//Display result of calculation
document.getElementById("output").innerText=Math.round(BMI*100)/100;
if (output<18.5)
document.getElementById("comment").value = "Underweight";
if (output>=18.5 && output<=25)
document.getElementById("comment").value = "Normal";
if (output>=25 && output<=30)
document.getElementById("comment").value = "Obese";
if (output>30)
document.getElementById("comment").value = "Overweight";
document.getElementById("answer").value = output;
}
</script>
</head>
<body>
<h1>Body Mass Index Calculator</h1>
<p>Enter your height: <input type="text" id="height"/>
<select type="multiple" id="heightunits">
<option value="metres" selected="selected">metres</option>
<option value="inches">inches</option>
</select>
</p>
<p>Enter your weight: <input type="text" id="weight"/>
<select type="multiple" id="weightunits">
<option value="kg" selected="selected">kilograms</option>
<option value="lb">pounds</option>
</select>
</p>
<input type="submit" value="computeBMI" onclick="computeBMI();">
<h1>Your BMI is: <span id="output">?</span></h1>
<h2>This means you are: value = "output" </h2>
</body>
最佳答案
嗨，我忘了说:D 它会起作用，你可以在第 23 行找到你的问题(在第一个答案编辑中:D)祝你好运
<!DOCTYPE html>
<html>
<head>
<title>BMI Calculator</title>
<script type="text/javascript">
function computeBMI() {
// user inputs
var height = Number(document.getElementById("height").value);
var heightunits = document.getElementById("heightunits").value;
var weight = Number(document.getElementById("weight").value);
var weightunits = document.getElementById("weightunits").value;
//Convert all units to metric
if (heightunits == "inches") height /= 39.3700787;
if (weightunits == "lb") weight /= 2.20462;
//Perform calculation
// var BMI = weight /Math.pow(height, 2)*10000;
var BMI = Math.round(weight / Math.pow(height, 2) * 10000);
//Display result of calculation
document.getElementById("output").innerText = Math.round(BMI * 100) / 100;
var output = Math.round(BMI * 100) / 100
if (output < 18.5)
document.getElementById("comment").innerText = "Underweight";
else if (output >= 18.5 && output <= 25)
document.getElementById("comment").innerText = "Normal";
else if (output >= 25 && output <= 30)
document.getElementById("comment").innerText = "Obese";
else if (output > 30)
document.getElementById("comment").innerText = "Overweight";
// document.getElementById("answer").value = output;
}
</script>`enter code here`
</head>
<body>
<h1>Body Mass Index Calculator</h1>
<p>Enter your height: <input type="text" id="height"/>
<select type="multiple" id="heightunits">
<option value="metres" selected="selected">metres</option>
<option value="inches">inches</option>
</select>
</p>
<p>Enter your weight: <input type="text" id="weight"/>
<select type="multiple" id="weightunits">
<option value="kg" selected="selected">kilograms</option>
<option value="lb">pounds</option>
</select>
</p>
<input type="submit" value="computeBMI" onclick="computeBMI();">
<h1>Your BMI is: <span id="output">?</span></h1>
<h2>This means you are: <span id="comment"> ?</span> </h2>
</body>
</html>关于javascript - 基本 BMI 计算器 HTML/Javascript，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21698044/