<html>
<head>
<script src="https://libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
$("button").click(function(){
alert("Image width: " + $("img").attr("width"));
});
});
</script>
</head>
<body>
<img src="/demo/img_pulpitrock.jpg" alt="Pulpit Rock" width="284" height="213">
<br>
<button>Return the width of the image</button>
</body>
</html>