![]()
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-type" content="text/html; charset=utf-8">
<title>Test page</title>
<script src="./jquery-1.11.1.min.js"></script>
<script>
$(document).ready(function() {
$(".btn-reduce").click(function() {
var a = $(".buy-num").val();
if (a - 1 > 0) {
$(".buy-num").attr("value", Number(a) - 1);
}
});
$(".btn-add").click(function() {
var a = $(".buy-num").val();
$(".buy-num").attr("value", Number(a) + 1);
});
});
function check(obj) {
if (isNaN(obj.value)) {
$(".buy-num").val("1");
}
}
</script>
</head>
<body>
<div class="wrap-input">
<a class="btn-reduce" href="javascript:;">-</a>
<input type="text" class="buy-num" id="buy-num" value="1" onkeyup="check(this);" />
<a class="btn-add" href="javascript:;">+</a>
</div>
</body>
</html>