timer_gear
exist only in case if I press some button (until 5 sec). But there is another function it can be called any time. In this function I clear the timer and restart it. But first I have to check if the object exists otherwise I get this error:
Uncaught ReferenceError: timer_gear is not defined
Could you help me to solve this? These does not work.
if(timer_gear!="undefined")clearTimeout(timer_gear);
if(timer_gear)clearTimeout(timer_gear);
EDIT1: first I misspelled my question: if(!timer => if(timer EDIT2:
the full code is:
function hide_gear(){
$('#gear_div').animate({opacity: 0}, 1000);
delete timer_gear; //EDIT3: destroy object
}
...
/*gear*/
$('#gear').click(function(){
$('#gear_div').animate({
opacity: 1,
}, 1000, function() {
timer_gear = setTimeout("hide_gear();",5000);
});
});
$('#gear').mousemove(function(){
if( ? ? ? )
{
clearTimeout(timer_gear);
timer_gear = setTimeout("hide_gear();",5000);
}
});
Results:
timer_gear// Uncaught ReferenceError timer_gear is not defined
timer_gear != undefined // Uncaught ReferenceError: timer_gear is not defined
typeof timer_gear !== "undefined" // WO开发者_如何转开发RKS
typeof timer_gear != "undefined" // WORKS, just tired it
var timer_gear; //at the begining - WORKS, but I did not wanted a new variable if its not necessary
thank you for answers!
All you need to do is declare timer_gear
. clearTimeout
is not the problem here. To quote the MDN; Passing an invalid ID to clearTimeout
does not have any effect (and doesn't throw an exception). So just add the following to the top of your code:
var timer_gear;
No need for all the if's that everyone else is suggesting.
If you only want to clear the timer held in the variable timer_gear
if it exists, you can do
if (timer_gear) clearTimeout(timer_gear);
The 1st one should be:
if(typeof timer_gear !== "undefined"){
clearTimeout(timer_gear);
}
And the 2nd, but this won't work if timer_gear
is not defined, so you should use the typeof
one above:
if(timer_gear){
clearTimeout(timer_gear);
}
You need a different condition on your if
:
if (typeof(timer_gear) !== "undefined")
or simply:
if (timer_gear)
Normally that should work:
timer_gear = false;
if(timer_gear != false){
clearTimeout(timer_gear);
}
if(timer_gear)clearTimeout(timer_gear);
or
if(timer_gear != undefined)clearTimeout(timer_gear);
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