I am trying to use the dev console to give mario a mushroom every 5 seconds (in the browser game super mario html5)
I can give mario mushrooms manually by typing marioShroons(mario) but I would like to have it on loop so I don't have to pause the game every time I want a mushroom. I have tried a while loop and set timeout but I can't figure it out. The only coding languages I familiar with are c++ and html.
**
while(data.time.amount > 0) {
killOtherCharacters()
}
setTimeout(function() {
killOtherCharacters()
}, 1000);
I expected these lines of code to not give me a mushroom, but to automatically kill enemies. But on the first try (the while loop) it froze the tab and I had to reload the page.
With the set timeout, it didn't make any obvious results, it killed all near characters once and then stopped.
You tried using setTimeout, and it only worked once. This is to be expected, because:
Window.setTimeout() sets a timer which executes a function or specified piece of code once the timer expires
From MDN
What you need to do is use setInterval:
The setInterval() method...repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.
From MDN
So in your console, you should write this:
setInterval(killOtherCharacters, 1000);
(I removed the anonymous function because it wasn't needed - you only need an anonymous function if you're passing parameters or doing multiple things. You do need to remove the () for this though).
And if you want to stop the function from executing, assign a variable to the interval:
var killCharacters = setInterval(killOtherCharacters, 1000);
Then call clearInterval upon this variable to clear the interval (stop the loop):
clearInterval(killCharacters);
The reason your while loop froze the page is because Javascript can only do one thing at a time and you told it to always run your while function, blocking all other Javascript from running on your site.
setTimeout is only run once after a set time (see documentation), if you want to run something every x miliseconds it's better to use setInterval instead.
var intervalID = window.setInterval(killOtherCharacters(), 500); //run this every 500 ms
Use setInterval if you want killOtherCharacters() to be called repeatedly.
const interval = setInterval(function() {killOtherCharacters() },1000);
Then when you want the function to stop being called:
clearInterval(interval);
Related
Personal project using jQuery.
I'm trying to create a function that runs on the hour for 5 seconds. I've done this by getting the current minutes and acting when they are at '00'. (Although for testing the minutes need to be manually changed to the next minute, unless you want to wait an hour to see it run again.)
The function acts on 2 objects, one to add/remove a class, the other to slideUp/Down.
It works, but after the initial running, the slideDown/Up jQuery causes a "blink" every 5 seconds for the rest of the current minute.
I've tried setting the setInterval for 5000, however that hasn't solved the issue. I'm at my wits end really.
While I am also using moment.js elsewhere. This function isn't using moment(). Primarily because I haven't been able to get functions working with moment() either.
Just head to the ....
jsFiddle example
Remember to set the =='00' to the next minute -- sure makes testing easier I really appreciate anyone waiting for this to run. I know it can be a pain to have to wait a minute to see the function at work.
If you watch the function run for 5 seconds, it will stop... but continue watching.. the slideDown() will repeat every 5 seconds until the minute is no longer XX.
How can I stop this repeat??
Thanks!
There're two place for fix.
1. miss usage for 'clearInterval'
clearInterval parameter is The ID of the timer returned by the setInterval() method.
reference this link, w3c definition for clearInterval.
var intervalId = setInterval(function() { alarm(); }, 5000);
...
clearInterval(intervalId );
2. secs >= "05" condition is wrong
change string "05" to int 5.
Believe it or not I sorted it a few moments after posting this.
My conditional was off, and I thought I tried everything. Guess not.
This works
if((mins == "29") && (secs <= '05')) {
$('#focus').slideDown(500);
$('.projcnt').addClass('jump');
} else {
$('#focus').slideUp(300);
$('.projcnt').removeClass('jump');
}
And the ...
working, updated fiddle
I am just finishing up a simon says game written with javascript/jquery. Everything is working okay, except for the playback sequence of simon after the second round. What happens is the new random button that simon presses decides to play as the second button in the playback sequence, when it should only be last (I say only because it does play at the end as well). I figure there is a discrepancy between the setTimeout and setInterval, but I am clueless as to what it is. Any ideas as to why this is happening? Here is my codepen for good measure: http://codepen.io/vinnyA3/pen/avvGbM?editors=001
(Press on, then start to start the game)
function playSimonSequence() {
var i = 0;
var myInterval = setInterval(function(){
//send in the correct button name and url to add the button pressed effect
lightsAndSounds(buttonsAndUrls[simonArray[i]].button, buttonsAndUrls[simonArray[i]].url);
++i;
if(i === simonArray.length){clearInterval(myInterval);}
},1500);
//this is running at the wrong time
setTimeout(randomButtonPress, 2210);
}; //end simon sequence
You have a 1500ms interval timer and a 2210ms single timer running at the same time. You should see the first interval at 1500ms, the single timer at 2210ms and then the second interval timer at 3000ms and so on. That's how your code has it specified.
Both your timers are running at the same time.
Javascript does not wait to run your setTimeout() until all the intervals are done. Instead, both timers are scheduled for their future time slot immediately and the run together.
If you want the setTimeout() to run after you clear the interval, then put the setTimeout() in the block of code where you call clearInterval().
I am trying to create a scenario where I have two variables (or more) both assigned to their own setInterval object and each setInterval object has a different function and a different millisecond value. The goal is to create a rhythm between the two by launching functions that play two different audio files repeatedly.
The current problem I've come across is this:
If one set interval is set to 1000 and the other is set to 500 each one doesn't start immediately. The millisecond delay is part of the start time. I want to know how to omit the delay on the start time so that both functions launch immediately but then they each keep there respective interval times.
The "logic" I've come up with so far is something along the lines of creating a function that immediately plays audio with no millisecond value and then have another function that is assigned to setInterval which begins playing x number of millisecond earlier on the next "beat" to make up the difference. I'm curious if the logic seems sound or if this is a problem in which a "conventional" javascript solution exist that I don't know about.It seems like there is an easier way.
I haven't begun coding yet albeit I didn't want to dig myself a hole before I have to if someone already has a fix for this.
Thanks
I avoid setInterval. Instead, i use setTimeout with such a pattern:
function someThing() {
// do something ...
setTimeout(someThing, 2000);
// or do something after setting the timeout ...
}
// either delay the start:
// setTimeout(someThing, 1000);
// or start right away
someThing()
But if you really want to use setInterval then a similar pattern works:
function someThing(firstTime) {
if (firstTime === true) {
console.log('setting interval for someThing');
setInterval(someThing, 1000);
}
console.log('someThing called');
}
someThing(true);
UPDATE 2:
OK, looks like it runs the first time after a minute. How do I get it to run onload, then every minute after that?
UPDATE 1:
I've tried: var interval = setInterval(get_reported_incidents, 60000); but nothing happens. in get_reported_incidents(); I just have an alert("hello");.
ORIGINAL QUESTION:
I want to run a function every minute:
get_reported_incidents();
But I am not sure which method is best for this task;
settimeout or setinterval
It's totally personal preference. setInterval has some odd edge cases around what happens when the previous interval's code hasn't finished running before the next interval is due to start (not a problem if your interval is every minute; intervals every second, which one sometimes wants, get a bit tricky).
I tend to prefer chained setTimeout calls (where each schedules the next) because they can't run away with you — your code always has to explicitly say "Okay, and call me back again next time." But properly-written code should work with either.
Chained setTimeout calls are also more well-suited to asynchronous operations, like for instance polling something via ajax, because you don't schedule the next timeout until the ajax operation completes. Using setInterval, because the ajax calls are asynchronous, you could end up overlapping them.
Using setinterval would be the more natural choise. If you use setTimeout, you have to start a new timeout from the event handler.
window.setInterval(get_reported_incidents, 60*1000);
setTimeout runs a command once after a period of time. setInterval runs a command every time interval.
So, to run get_reported_incidents every minute use setInterval.
var interval = setInterval(get_reported_incidents, 60000);
setinterval executes a function at a given interval. settimeout executes a function after a specified wait time, and then exits.
If you are attempting to do a cron-like execution every minute, you will want to use setinterval.
Please see http://javascript.about.com/library/blstvsi.htm for a comparison.
use setTimeout recursively. See here for more information on why setInterval is a poor choice.
function timeout (){
get_reported_incidents();
setTimeout(timeout, 1000 * 60);
}
timeout(); // start
Strictly speaking, setInterval() was designed for repeating events and setTimeout() for one-shot events.
However you will tend to find that with setTimeout() time will "creep" gradually. I've not tried this at 1 minute intervals, but with a 1 second timer I found it happened quite a lot. A clock showing the current time (to the nearest millisecond) would show a steady increase in the millisecond value of "now".
See http://jsfiddle.net/alnitak/LJCJU/ and tweak the interval to see what I mean!
So, for greatest accuracy, I do this:
var timerHandler = function() {
var interval = 60000;
// do some stuff
...
var now = new Date();
var delay = interval - (now % interval);
setTimeout(timerHandler, delay);
};
This is ideal if you want the timer events to be started in sync with the clock on your system, rather than at some unspecified time "roughly every minute".
obviously setinterval might be easier to maintain in your case
get_reported_incidents(); //first call
var interval = setInterval(get_reported_incidents, 60000);
vs
var interval;
function timeout (){
get_reported_incidents();
interval=setTimeout(timeout, 60000);
}
timeout();
a question. If i use setInterval in this manner:
setInterval('doSome();',60000);
am i safe that the doSome() function is triggered every 60 seconds, even if I change the tab in a browser?
Passing a string to setInterval is fine, and is one of two ways to use setInterval, the other is passing a function pointer. It is not wrong in any way like the other answers state, but it is not as efficient (as the code must be reparsed) nor is it necessary for your purpose. Both
setInterval('doSome();', 60000); // this runs doSome from the global scope
// in the global scope
and
setInterval(doSome, 60000); // this runs doSome from the local scope
// in the global scope
are correct, though they have a slightly different meaning. If doSome is local to some non-global scope, calling the latter from within the same scope will run the local doSome at 60000ms intervals. Calling the former code will always look for doSome in the global scope, and will fail if there is no doSome function in the global scope.
The function will reliably be triggered, regardless of tab focus, at intervals of at least 60000ms, but usually slightly more due to overheads and delays.
All browsers clamp the interval value to at least a certain value to avoid intervals being too frequent (I think it's a minimum of 10ms or 4ms or something, I can't exactly remember).
Note that some browsers (the upcoming Firefox 5 is one, but there are probably others that I don't know of) further clamp setInterval drastically to e.g. 1000ms if the tab is not focused. (Reference)
No, the interval cannot execute until the event loop is cleared, so if you do for instance setInterval(func, 1000); for(;;) then the interval will never run. If other browsers tabs run in the same thread (as they do everywhere(?) except for in chrome, then the same applies if those tabs clog the event loop.)
But for an interval as large as 60000 it is at least very likely that the func will be called in reasonable time. But no guarantees.
If the tab with the setInterval() function remains open, then yes the function will be executed every 60 seconds, even if you switch to or open other tabs.
Yeah it works on an example I just created.
http://jsfiddle.net/5BAkx/
Yes, the browser's focus is irrelevant.
However, you should not use a string argument to setInterval. Use a reference to the function instead:
setInterval(doSome, 60000);
No, you are not guaranteed exact time safety. JS is event based (and single-threeaded) so the event won't fire at the exact right moment, especially not if you have other code running at the same time on your page.
The event will fire in the neighbourhood of the set time value, but not on the exact millisecond. The error may be tens of milliseconds even if no other event is running at the time. This may be an issue if for example you have a long-running process where the timing is important. If you do, you'll need to synchronize with a clock once in a while.
Yes it will be called as long as the page is open, regardless the tab is switched or even the browser is minimized.
However make sure you pass the function not a string to setInterval
it should be >
setInterval(doSome, 60000)
About "exact time safety": The following code starts UpdateAll at intervals of RefreshInterval milliseconds, with adjustment each second so that one start occurs at each second at the start of the second. There will be a slight delay for the finite speed of the computer, but errors will not accumulate.
function StartAtEachSecond ()
{
var OneSecond = 1000; // milliseconds
var MinInteral = 50; // milliseconds, estimated safe interval
var StartTime = OneSecond - (new Date ()).getMilliseconds (); // Time until next second starts.
if (StartTime < MinInteral) StartTime += OneSecond
window.setTimeout (StartAtEachSecond, StartTime + MinInteral); // To set up the second after the next.
for (var Delay = 0.0; Delay < OneSecond - MinInteral; Delay += RefreshInterval)
{
window.setTimeout (UpdateAll, StartTime + Delay); // Runs during the next second.
}
}