The pit between the old version of jquery and the new version

jquery has been adding properties since the 1.6.1 version, using these new properties whenever possible, such as: selected, checked. It is best to use prop when assigning values in a higher version, and if you use attr, the assignment is unsuccessful.

General custom attributes with attr, intrinsic properties with prop

The following are the official recommendations for the use of attr (), prop ():

Attribute/property	.attr()	.prop()
AccessKey	√
Align	√
Async	√	√
Autofocus	√	√
Checked	√	√
Class	√
Contenteditable	√
Draggable	√
Href	√
Id	√
Label	√
Location (i.e. window.location)	√	√
Multiple	√	√
ReadOnly	√	√
Rel	√
Selected	√	√
Src	√
TabIndex	√
Title	√
Type	√
Width (if needed over .width() )	√

A pit between old versions of the new jquery version