Выберите элемент LI с клавишами со стрелками (вверх и вниз), используя JavaScript
var li = $('#list > li');
var liSelected;
$(window).on('keydown', function(e){
var selected;
if(e.which === 40){
if(liSelected){
liSelected.removeClass('background');
next = liSelected.next();
if(next.length > 0){
liSelected = next.addClass('background');
selected = next.text();
}else{
liSelected = li.eq(0).addClass('background');
selected = li.eq(0).text();
}
}else{
liSelected = li.eq(0).addClass('background');
selected = li.eq(0).text();
}
}else if(e.which === 38){
if(liSelected){
liSelected.removeClass('background');
next = liSelected.prev();
if(next.length > 0){
liSelected = next.addClass('background');
selected = next.text();
}else{
liSelected = li.last().addClass('background');
selected = li.last().text()
}
}else{
liSelected = li.last().addClass('background');
selected = li.last().text()
}
}
console.log(selected)
});
/*HTML FILE CODE
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title></title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<link rel="stylesheet" href="">
<style>
.background{
background: hsla(0, 100%, 0%, 0.4);
}
</style>
</head>
<body>
<input type="text" class="form-control" id="searchProduct" placeholder="Search..." />
<ul id="list">
<li id="match1" class="itemList">1</li>
<li id="match2" class="itemList">2</li>
<li id="match3" class="itemList">3</li>
</ul>
</body>
</html>
*/
Dentetsu