Javascript Sleep Function
I’ll make this short and quick. I’ve been searching the web for a Javascript sleep function that works and came across this. It was presented as a class but what I needed was just a function so I rewrote the code a bit. Here’s the end result of my Javascript sleep function which I named, well, jsleep.
function jsleep(s){
s=s*1000;
var a=true;
var n=new Date();
var w;
var sMS=n.getTime();
while(a){
w=new Date();
wMS=w.getTime();
if(wMS-sMS>s) a=false;
}
}
// how to use
alert('in the beginning there was a pause...');
jsleep(3);
alert('3 seconds after... the pause was gone.');
I’ve tested it in Google Chrome, Firefox 3 and Internet Explorer 7. Works like a charm.
Hi Mike,
I couldn’t find anywhere to contact you so i thought i would do it through here. I know your blog is mainly on coding but noticed you posted some great tech posts such as the new mac video and thought a new video piece i am working on might be of interest to you. Its about a dysfunctional managers resistance to installing an ERP system. Although the video is really funny it does highlight some serious points.
http://www.k3scs.com/the-factory/
I thought it would point it out to you and if you have any feedback please let us know. Please also feel free to use the video.
Thanks
Mark
hi,
Thanks a lot for the code. I think lots of people are looking for this. Btw where do I find the class file for this?
regards,
Harish
This is a terrible implementation. The while loop will completely dominate the CPU and hang the browser until sleep is done. On Firefox, if you sleep for longer than 5 or 10 seconds, this will cause an ugly warning dialog because the browser will think the script is stuck in an infinite loop.
There is no JavaScript sleep() function. (Which I find to be a huge flaw with the langauge.) Instead, you should use setTimeout(). Google “JavaScript sleep” to find what other people have said on this topic, but a loop that polls the current time is NOT what you want.
I have searched/googled quite a few webpages on javascript sleep/wait… and there is NO answer if you want javascript to “RUN, DELAY, RUN”… what most people got was either, “RUN, RUN(useless stuff), RUN” or “RUN, RUN + delayed RUN”….
So I ate some burgers and got thinking:::
here is a solution that works… but you have to chop up your running codes…:::
replace <.. with < to run..
//…………………………………..
//example1:
DISPLAY
//javascript sleep by “therealdealsince1982″; copyrighted 2009
//setInterval
var i = 0;
function run() {
//pieces of codes to run
if (i==0){document.getElementById(“id1″).innerHTML= “code segment “+ i +” is ran”; }
if (i==1){document.getElementById(“id1″).innerHTML= “code segment “+ i +” is ran”; }
if (i==2){document.getElementById(“id1″).innerHTML= “code segment “+ i +” is ran”; }
if (i >2){document.getElementById(“id1″).innerHTML= “code segment “+ i +” is ran”; }
if (i==5){document.getElementById(“id1″).innerHTML= “all code segment finished running”; clearInterval(t); } //end interval, stops run
i++; //segment of code finished running, next…
}
t=setInterval(“run()”,1000);
//………………………………
//example2:
DISPLAY
//javascript sleep by “therealdealsince1982″; copyrighted 2009
//setTimeout
var i = 0;
function flow() {
run(i);
i++; //code segment finished running, increment i; can put elsewhere
sleep(1000);
if (i==5) {clearTimeout(t);} //stops flow, must be after sleep()
}
function run(segment) {
//pieces of codes to run, can use switch statement
if (segment==0){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment==1){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment==2){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment >2){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
}
function sleep(dur) {t=setTimeout(“flow()”,dur);} //starts flow control again after dur
flow(); //starts flow
//……………………………….
//example3:
DISPLAY
//javascript sleep by “therealdealsince1982″; copyrighted 2009
//setTimeout, switch
var i = 0;
function flow() {
switch(i)
{
case 0:
run(i);
sleep(1000);
break;
case 1:
run(i);
sleep(2000);
break;
case 5:
run(i);
clearTimeout(t); //stops flow
break;
default:
run(i);
sleep(3000);
break;
}
}
function run(segment) {
//pieces of codes to run, can use switch statement
if (segment==0){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment==1){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment==2){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
if (segment >2){document.getElementById(“id1″).innerHTML= “code segment “+ segment +” is ran”; }
i++; //current segment of code finished running, next…
}
function sleep(dur) {t=setTimeout(“flow()”,dur);} //starts flow control again after dur
flow(); //starts flow control for first time…
This is not a solution for me… I’m trying to avoid the IE script warning that occurs when a few million javascript operations occur… this can be done by setTimeout() but I seem to also require a true javascript sleep() function. Your jsleep() routine doesn’t help since it simply chugs through a loop at lightning speed. Have you tried your jsleep() on IE for a few seconds? I have little doubt it craps out.
I like the code.