How can i add extra field on this select wrapper form?

[Sebszty]

Now i can print id & text, i want to store and print one more value "extra". If it is possible?

data:[ {id:0,text:"asda",extra:"one"}, {id:1,text:"adasdas",extra:"two"}, ],

[rkit]

If you about data-* attributes:

{ text: 'documents', id: 3, 'data-prop': 'val' },