Unable to update variable value inside setInterval

Asked Dec 05 '19 at 07:39

Active Dec 05 '19 at 07:39

Viewed 26 times

I want to keep track of a count variable inside the callback function for setInterval but the incremented value does not seem to pass down after each call. Here is my code:

var count = 0;
function open_link(count) {
    $("a")[count].click();
    count++;
}
setInterval(open_link, 5000, count);

I was expecting that count will be 0, 1, 2 and so on but the value of count always stays 0. How can I update it?

Thanks.

asked Dec 05 '19 at 07:39

Real Noob

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Your `count` is a parameter, so it's a local variable, so reassigning it doesn't have any effects elsewhere (like on subsequent calls). Remove it from the parameter list so that the outer `count` is affected instead – CertainPerformance Dec 05 '19 at 07:41
@CertainPerformance Are variables outside the function accessible inside them? – Real Noob Dec 05 '19 at 07:43
1

@RealNoob yes if they are global variables. – Himanshu Singh Dec 05 '19 at 07:44
2

Yes, except in this type of situation, where the outer variable is being shadowed by an inner one (in which case, only the inner one will be visible inside) – CertainPerformance Dec 05 '19 at 07:44
Thank you. Things work differently in PHP so I was confused. :) – Real Noob Dec 05 '19 at 07:46
1

@HimanshuSingh You can access any variable when it is declared in the outer scope chain, it doesn't need to be a global variable. – Teemu Dec 05 '19 at 08:02

Unable to update variable value inside setInterval

0 Answers0