Is it possible to declare variable dynamically in jquery as a global variable?

Question

So i want to declare variable according to my loop. so i have done the following

 $.each(filter,function(key,value){
    var value;
   });

my filter array contains:

Geo_Name_date,Geo_Gender_date,Geo_Age_date,Geo_Ethnicity_date,Geo_Race_date,Geo_Language_date,Geo_Smoker_ind_date,Geo_Primarycare_provider_name_date

When i alert after the loop over. the variable should alert undefined. But its giving reference error. any suggestion or what am doing wrong? is it possible to do like this?

`value` is a local variable in the function. After the loop is done, the variable is gone. — Barmar, Sep 25 '14 at 06:57
you are getting `value` as parameter in `function(key,value)` and you are trying to define `value` again that you cannot. try some other name. — Bhushan Kawadkar, Sep 25 '14 at 06:57
Yea just now found that. Can you provide me some suggestion on getting that globally. — divakar, Sep 25 '14 at 06:57
If you want to create a global variable, don't use the `var` keyword, and use a different name than the parameter. — Barmar, Sep 25 '14 at 06:57
`this.a= 0;` or `window.a = 0;` see: [javascript-global-variables](http://stackoverflow.com/questions/4862193/javascript-global-variables) — Stefan Friedrich, Sep 25 '14 at 07:01

score 1 · Answer 1 · answered Sep 25 '14 at 06:58

1

To assign a global variable, leave out the var keyword:

$.each(filter, function(key, value) {
    globalValue = undefined;
});
alert(globalValue); // Will show undefined

answered Sep 25 '14 at 06:58

Barmar

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Hey Barmar, So i have tried something like this but it not seems to be working. $.each(filter,function(key,value){ value=undefined; }); alert(Geo_Name_date); – divakar Sep 25 '14 at 07:03

score 1 · Accepted Answer · answered Sep 25 '14 at 07:06

You should preferably create properties in an object rather than global variables:

var values = {};
$.each(filter, function(key, value) {
  values[value] = undefined;
});

It's possible to create global variables dynamically. You should avoid creating a lot of variables in the global scope, but if that is really what you need, you can use the eval method to assign values to the variables in the loop without declaring them. That will create them in the global scope:

$.each(filter, function(key, value) {
  eval(value + '=undefined');
});

Is it possible to declare variable dynamically in jquery as a global variable?

2 Answers2