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#8288 closed bug (wontfix)
Opened February 15, 2011 09:44PM UTC
Closed February 15, 2011 11:19PM UTC
Last modified May 08, 2011 06:18AM UTC
.data(key) no longer returning null?
| Reported by: | contact@alanhogan.com | Owned by: | |
|---|---|---|---|
| Priority: | high | Milestone: | 1.next |
| Component: | data | Version: | 1.5 |
| Keywords: | Cc: | ||
| Blocked by: | Blocking: |
Description
I just upgraded to jQuery 1.5.0 from 1.4.2, I think it was. I previously had code that relied upon this documented behavior of .data(key).
From http://api.jquery.com/data/#data2 —
“If nothing was set on that element, null is returned.”
Thus, I could do:
if($('#foo').data('my_key') === null) {
// calculate & set it…
}
In jQuery 1.5.0, this seems to be returning 'undefined' instead.
Attachments (0)
Change History (6)
Changed February 15, 2011 09:50PM UTC by comment:1
| _comment0: | Confirmed \ \ http://jsfiddle.net/rwaldron/pHTP4/1/ → 1297806636513271 |
|---|---|
| component: | unfiled → data |
| priority: | undecided → high |
| status: | new → open |
Changed February 15, 2011 10:21PM UTC by comment:2
| keywords: | → needsdocs |
|---|
Update docs to read:
If nothing was set on that element, undefined is returned.
Code should be updated accordingly
Changed February 15, 2011 11:19PM UTC by comment:3
| resolution: | → wontfix |
|---|---|
| status: | open → closed |
This won't be fixed. .data() only returned null in some very specific circumstances. And the behavior didn't make much sense the way it was.
var x = $("elem1");
x.data("foo"); // null
var y = $("elem2");
y.data(); // {}
y.data("foo"); // undefined
var z = $("elem3");
z.data("bar", "tender");
z.data("foo"); //undefined
So null was only returned if there was no data at all on the element. But it returned undefined if there was already some other data.
Changed February 15, 2011 11:57PM UTC by comment:4
1) I’m not seeing the change to the docs. Is there a delay?
2) Okay, I’m all for consistency. Shouldn’t this be noted somewhere, though? Added to the changelog perhaps?
Changed February 16, 2011 12:01AM UTC by comment:5
Hmm, seems the change was actually between 1.4.2 and 1.4.4.
Changed May 08, 2011 06:18AM UTC by comment:6
| keywords: | needsdocs |
|---|
Updated needsdocs: http://api.jquery.com/data/. Now includes changed verbiage to correct what is now being returned as well as a minor example.
Confirmed
1.4.2 http://jsfiddle.net/rwaldron/pHTP4/1/
1.5.0 http://jsfiddle.net/rwaldron/pHTP4/2/