Tizen Developers

Try

( interval === undefined )

Thanks.

Well you can do

var interval = setInterval(function() {}, 1000);
interval = clearInterval(interval);
if (typeof interval === 'undefined'){

}

but what are you actually trying to do? clearInterval function is an always success function and it will always return undefined even if you call it with a NaN value, no error checking in there.

var interval = 0;

interval = setInterval(function() {}, 1000);

clearInterval(interval);

console.log(typeof interval); // get the type

Javascript is a pass by value language, meaning whatever you do with the parameter inside the function, it won't change the value of the variable inside the caller function. So interval variable stays with the same value after you call clearInterval.

Did you wrote interval  = clearInterval(interval); ? This should set interval to undefined thus typeof interval === 'undefined' should work.