About jQuery append() and how to check if an element has been appended

Question

I made a very simple button click event handler, I would like to have

element be appended when button clicked, you can check my code

Answer 1

1. You are using mootools and not jQuery.

2. To check if your element exists

if($('#other').length > 0)

So if you do not want to append the element twice:

$("#search_btn").click(function() {
    if($('#other').length == 0) {
        $("#wrapper").append("
I am here
");
    }
});

Or, you can use the .one(function)[doc]:

$("#search_btn").one('click', function() {
    $("#wrapper").append("
I am here
");
});