width,clientWidth,offsetWidth

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<script>
window.onload = function() {
    
    var oDiv = document.getElementById('div1');
    
    /*
        width height
        style.width : 样式宽
        clientWidth : 可视区宽
        offsetWidth    : 占位宽
    */
    
    alert( oDiv.style.width );    //100
    alert( oDiv.clientWidth );    //样式宽 + padding    120
    alert( oDiv.offsetWidth );    //样式宽 + padding + border  可视区宽 + 边框    122
    
}
</script>
</head>

<body>
    <div id="div1" style=" 100px; height: 100px; border: 1px solid red; padding: 10px; margin: 10px;"></div>
</body>
</html>

height

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<script>
window.onload = function() {
    
    var oDiv = document.getElementById('div1');
    
    /*
        width height
        style.height : 样式高
        clientHeight : 可视区高
        offsetHeight : 占位高
    */
    
    alert( oDiv.style.height );    //100
    alert( oDiv.clientHeight );    //样式高 + padding    120
    alert( oDiv.offsetHeight );    //样式高 + padding + border  可视区高 + 边框    122
    
}
</script>
</head>

<body>
    <div id="div1" style=" 100px; height: 100px; border: 1px solid red; padding: 10px; margin: 10px;"></div>
</body>
</html>
原文地址:https://www.cnblogs.com/Xuman0927/p/5501210.html