Assign variable value as variable name

Question

the problem is i want to shorten my code by calling a variable using other variable's value

long working version:

var russia = new Array('15')
var switzerland = new Array('5')

$('.country').mouseover(function(){
    switch(this.id){
        case 'russia':
            active_country_lift(this.id,russia[0])
        break
        case 'switzerland':
            active_country_lift(this.id,switzerland[0])
        break           
    }
})

it will get the id of mouseovered then check if it matched one of the variable by using switch

what i want to obtain is something like this:

var russia = new Array('15')
var switzerland = new Array('5')

$('.country').mouseover(function(){
    active_country_lift(this.id,this.id[0])     
})

of course the above code wouldn't work but is there a workaround for this?

UPDATE: Arun's answer worked and ill accept it soon and as for the comments requesting for the full code, here's a chunk of it after i applied Arun's

var countries = {
    russia: ['-15px'],
    switzerland: ['-5px']
}

$('.country_inactive').mouseover(function(){
    active_country_lift(this.id, countries[this.id][0])
})

function active_country_lift(country, country_top){
    if(!$('#'+country+'_active').hasClass('active')){
        $('#'+country+'_active').stop().fadeIn(100).animate({
            'top' : country_top
        }, 200)
        $('#'+country).stop().fadeOut(100)
    }
}

it will be used for a world map, feel free to make any suggestions for making it more dynamic

Pro tip: never use new Array in JS unless you are declaring the length of the array. Just initialize the array using []. — Matthew Herbst
– Matthew Herbst, Commented Apr 22, 2016 at 3:36
Can you add complete code of what you're trying to achieve, this can probably achieved using CSS only. — Tushar
– Tushar, Commented Apr 22, 2016 at 3:40
Possible duplicate of Get global variable dynamically by name string in JavaScript — castletheperson
– castletheperson, Commented Apr 22, 2016 at 3:59

Arun P Johny · Accepted Answer · 2016-04-22 03:38:43Z

4

You can store the country info in an object like a key value pair, then use bracket notation to access it dynamically

var countries = {
  russia: new Array('-15px'),
  switzerland: new Array('-5px')
}

$('.country').mouseover(function() {
  active_country_lift(this.id, countries[this.id][0])
})

If you don't have multiple values then

var countries = {
  russia: '-15px',
  switzerland: '-5px'
}

$('.country').mouseover(function() {
  active_country_lift(this.id, countries[this.id])
})

edited Apr 22, 2016 at 3:38

answered Apr 22, 2016 at 3:35

Arun P Johny

389k68 gold badges532 silver badges532 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Tushar Over a year ago

new Array('-15px') ==> '-15px'. Why use array.

Matthew Herbst Over a year ago

@Tushar it actually gives ['-15px']

Arun P Johny Over a year ago

@Tushar there could be multiple values, not sure about that

castletheperson Over a year ago

If russia and switzerland are globals, you could even just do window[this.id] instead of creating a wrapping object, but creating a wrapping object is better because global variables are bad practice.

Tushar Over a year ago

@4castle yes, you can. But using object is better practice instead of globals

|

Developer107 · Accepted Answer · 2016-04-22 03:46:19Z

0

try using eval() function

var russia = new Array('-15px')
var switzerland = new Array('-5px')

$('.country').mouseover(function(){
   active_country_lift(this.id,eval(this.id)[0])     
})

edited Apr 22, 2016 at 3:46

answered Apr 22, 2016 at 3:37

Developer107

1,7582 gold badges14 silver badges24 bronze badges

1 Comment

castletheperson Over a year ago

Most people pronounce eval as evil because it is evil and inefficient. This is a valid answer though.

Collectives™ on Stack Overflow

Assign variable value as variable name

2 Answers 2

6 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related