output
output 标签定义不同类型的输出，比如脚本的输出。例如：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Chapter3</title>
<style type="text/css">
label{
display: inline-block;
60px;
}
</style>
<script type="text/javascript">
function CalculateBMI(feet,inches,pounds,resultElementName){
inches=Number(inches)
pounds=Number(pounds)
feet=Number(feet)
var totalInches=(feet*12)+inches
var resultElement=document.getElementById(resultElementName)
resultElement.innerHTML=Math.round(pounds*703*10/totalInches/totalInches)/10
}
</script>
</head>
<body>
<h1>Body Mass Index Calculator</h1>
<form action="#" id="bmiCalculator">
<label for="feet inches ">Height:</label>
<input name="feet">feet<br>
<label></label>
<input name="inches">inches<br>
<label for="pounds">Weight:</label>
<input name="pounds">pounds<br><br>
<input type="button" name="calc" value="Calculate" onclick="CalculateBMI(this.form.feet.value,this.form.inches.value,this.form.pounds.value,'result')">
</form>
<p>Your BMI:<output id="result"></output></p>
<table cellpadding="5" cellspacing="0" border="1">
<tr>
<td><b>BMI</b></td>
<td><b>Weight Status</b></td>
</tr>
<tr>
<td>Below 18.5</td>
<td>Underweight</td>
</tr>
<tr>
<td>18.5 – 24.9</td>
<td>Normal</td>
</tr>
<tr>
<td>25.0 – 29.9</td>
<td>Overweight</td>
</tr>
<tr>
<td>30.0 and Above</td>
<td>Obese</td>
</tr>
</table>
</body>
</html>