试一试 - JavaScript Reference element_clientheight

<!DOCTYPE html>
<html>
<head>
<style>
#myDIV {
    height: 250px;
    width: 400px;
    padding: 10px;
    margin: 15px;
    border: 5px solid red;
    background-color: lightblue;
    overflow: auto;
}

#myDIV2 {
    height: 250px;
    width: 400px;
    padding: 10px;
    margin: 15px;
    border: 5px solid red;
    background-color: lightblue;
}

#content {
    height: 800px;
    width: 2000px;
    background-color: lightyellow;
}
</style>
</head>
<body>

<p>In this example, the child element (#content) inside the first div is bigger than div's height and width 
(the child is 800x2500 while its parent is 250x400), so we have added a scrollbar.</p>

<p>Click the button to get the clientHeight, offsetHeight, clientWidth and offsetWidth of div.</p>

<p>Notice how the scrollbar in the first div "steals" some of div's right and bottom padding, which results in a lower return value for clientHeight and clientWidth in that div, compared to the other one. The offsetHeight and offsetWidth is not affected by this.</p>

var elmnt2 = document.getElementById("myDIV2");
    var txt2 = "";
    txt2 += "<b>Information about div2:</b><br>";
    txt2 += "Height including padding: " + elmnt2.clientHeight + "px<br>";
    txt2 += "Height including padding and border: " + elmnt2.offsetHeight + "px<br>";
    txt2 += "Width including padding: " + elmnt2.clientWidth + "px<br>";
    txt2 += "Width including padding and border: " + elmnt2.offsetWidth + "px";
    document.getElementById("content2").innerHTML = txt2;
}
</script>

</body>
</html>