<html>
<head>
<title>二重送信を防ぐ</title>
<style>
.btn-wrap {
width: 300px;
margin: 0 auto;
text-align: center;
}
.loading {
display:none;
}
</style>
</head>
<body>
<div class="btn-wrap">
<button class="btn">送信</button>
<div class="loading">
<img src="loading.gif">
</div>
</div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(function(){
$('.btn').on('click', function(){
$('.btn').hide();
$('.loading').show();
});
});
</script>
</body>
</html>
