disable "mark as read" button
I just recently started delving into ajax and jquery. I have an image that "marks an item as read" and that seems to be working, how can I disable the image so if it is clicked again it will do nothing? The image dims to invisible.... I tried setting it's attribute to disabled like the faq's suggest but I am doing something wrong.
$(".markasread").click(function() {
$(this).fadeTo("fast", Math.random());
//extract topic_id, to send with POST request
var $topicid = $(this).attr('id').split('_');
//make the POST request
$.post('handlemarkasread.php', { topicid: $topicid[1] });
$(".markasread").attr("disabled","disabled");
});
<img src="images/buttons/plus.png" class="markasread" onclick="$('.markasread').attr('disabled','disabled')" />