# How to add scrollbars to a block (e.g. a <div> element)

If you need to customize a list box then the <select> HTML element might not be enough. In such a case you’d like to have something that simulates the <select> behaviour.

Here is the code to use to obtain a custom list box:


<html>

<body>
<div style="width: 200px; height: 200px; overflow: auto;">
<table width="100%" height="100%">
<script>
for (var i = 0; i < 30; i++) {
if (i % 2 == 0) {
document.write(
"<tr style='background-color:#0066ff; color: #ffffff'>" +
"<td>JavaScript</td></tr>");
}
else {
document.write(
"<tr style='background-color:#ff6600; color: #ffffff'>" +
"<td>JavaScript</td></tr>");
}
}
</script>
</table>
</div>
</body>
</html>

The key CSS element is overflow. If you use overflow: auto then the scrollbars are displayed only if they are needed. If you want to display them in any case then you need to use overflow: scroll.