Conditionally set an HTML attribute
I had to conditionally set an attribute while building the HTML of a page.
In particular I wanted to add the selected
attribute to an option in a select based on the URL.
I couldn’t say selected={true}
, where true is determined with JavaScript, because the mere existence of selected=
makes the browser consider the option as selected. So the end result is the last option is always selected by default.
Here’s what I ended up doing:
<select>
{teams.map((team) => {
const attributes = {
...(Astro.url.pathname.includes('/team/') &&
Astro.params.id === team.id && { selected: 'selected' }),
}
return (
<option {...attributes} value={`/team/${team.id}`}>
{team.name}
</option>
)
})}
</select>
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