Cannot call method 'attr' of undefined class jQuery

Question

HTML

<input type="number" id="progress-update-1234" class="progress-update" data-entryid="1234" data-updateItem="progress" value="3" min="1" max="15" />

jQuery

$( ".progress-update" ).change(function() {

    var entry_id = this.$.attr('data-entryid');
    var item_entry = this.$.attr('data-updateItem');
    var new_progress = $("#progress-update-" + entry_id).val();

    alert( "This is progress update" + entry_id + " and type " + item_entry + " and new progres " + new_progress );
});

I'm not exactly sure why this is returning an error: Cannot call method 'attr' of undefined in the console. I am using this inside the change function that is attached to the right class. Why am I getting this error?

http://stackoverflow.com/questions/20856236/jquery-knob-release-function-additional-parameter — Maaz, Jan 01 '14 at 23:22
Take a look at this question, which I also asked and some how `this.&` is working over `$(this)` — Maaz, Jan 01 '14 at 23:23
That's a weird property that the jQuery Knob plugin author decided to set. — Blender, Jan 01 '14 at 23:25

score 1 · Answer 1 · answered Jan 01 '14 at 23:22

1

Use it like this:

var entry_id = $(this).attr('data-entryid');

attr is a jQuery function that's why it can use only with jQuery objects. this not a jQuery object but $(this) is.

answered Jan 01 '14 at 23:22

Selman Genç

100,147
13
119
184

score 1 · Answer 2 · answered Jan 01 '14 at 23:22

1

your code should look like this

var entry_id = $(this).attr('data-entryid');

answered Jan 01 '14 at 23:22

Damien Black

5,579
18
24

score 1 · Answer 3 · answered Jan 01 '14 at 23:23

1

You must wrap the element with jQuery

var entry_id = $(this).attr('data-entryid');
var item_entry = $(this).attr('data-updateItem');

answered Jan 01 '14 at 23:23

Kevin Bowersox

93,289
19
159
189

Cannot call method 'attr' of undefined class jQuery

3 Answers3