Declaring global variables 2

[Sleidia]

Hi guys

Is it possible to declare a variable global from inside a function?

How do you make sure a global variable will never be polluted (ie:duplicate name) by a foreign script also using global variables?

Thanks!

 

[BabyJeffy]

You can declare a global variable from within a function by using the window array:

function foo() {
  window['bar'] = 'wibble';
}

The variable is now able to be referenced as either "wibble" or "window['wibble']".

Cheers,
Jeff

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[Sleidia]

Thanks

So, to answer the second question, woudn't it be wise to have something like this? :

function my_function() {

window['my_function']['my_var'] = 'my value';

}

 

[BillyRayPreachersSon]

You can also declare a global variable inside a function simply by omitting the "var" keyword:

function wibble() {
   abc = 1; // this will be global
   var def = 2; // this will be local
}

You can't stop a foreign script from overwriting your own global variables, but you can test whether a foreign script is using a variable or not:

if (typeof(window['globalVariableName']) == 'undefined') {
   // it's same to use 'globalVariableName' now...
}

Hope this helps,
Dan



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[BillyRayPreachersSon]

"same" should have read "safe" in the comment in my last post...

Dan



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[Sleidia]

Very nice, thanks