Make the clock decrement

Question

Hey guys am trying to get an expected download time with an ajax script..It just works fine ..I get the expected time in the format hh:mm:ss.But the clock isnt moving The code i have tried

function get_filesize(url, callback) {
var xhr = new XMLHttpRequest();
xhr.open("HEAD", url, true);
xhr.onreadystatechange = function() {
    if (this.readyState == this.DONE) {
        callback(parseInt(xhr.getResponseHeader(
            "Content-Length")));
    }
};

xhr.send();

}


get_filesize(
"http://upload.wikimedia.org/wikipedia/commons/9/96/Google_web_search.png",
function(size) {
    var estimatedtime = (new Date().getTime()) / size;
    var time = new Date(estimatedtime);
    var c = setTimeout(function() {
        time.getHours() + ":" + time.getMinutes() + ":" +
            time.getSeconds()
    }, 500);

    console.log(c);

});

When i try this code i get an output like 1.

What i need as my output

Suppose the output i got is 00:57:12 i need to decrement the time as a timer like 00:57:11 ans so on.

I havnt no idea on how to try this ..i have tried setTimeout But it didnt helped me.

Any help would be greatly appreciated..Thanx

I'm a bit confused about how you calculate your estimated time? You get the current time and divide it by the file size? Doesn't make any sense to me. — Dimitar Dimitrov, Dec 15 '14 at 09:11
Regardless the logic of how you get the estimated time, just want to point out that if you using setTimeout, it only will run once after you trigger the get_filesize function. If you want the timer to keep decreasing, you should use setInterval as per suggested by @ykc which it will run on every x milliseconds. Besides that, I found that you never update your time variable. The code in setTimeout will run but it will keep show the same value. — Joey Chong, Dec 15 '14 at 09:11
@JoeyChong thanx man .can you tell me how can i get the transfer rate if an item is downloading ??..is transfer rate == bandwidth of my connection at download time ?? — lovejs, Dec 15 '14 at 13:25
@JoeyChong i have searched all over but i couldnt find it ??..is the transfer rate equals to my bandwidth speed at time of download ? — lovejs, Dec 15 '14 at 15:31
I thought I had give you some references on your previous post? Anyways, you also can refer to this [detect internet speed](http://stackoverflow.com/questions/5529718/how-to-detect-internet-speed-in-javascript) — Joey Chong, Dec 16 '14 at 01:22

ykc · Accepted Answer · 2014-12-15T12:30:10.810

0

You may try setInterval instead of setTimeout :

setInterval(function() {
   var c = time.getHours() + ":" + time.getMinutes() + ":" +
        time.getSeconds();
   console.log(c);
}, 500);

Edit : I updated the code above

edited Dec 15 '14 at 12:30

answered Dec 15 '14 at 08:41

ykc

63
1
6

i get the same output which is 1 when i run this code – lovejs Dec 15 '14 at 11:20
can you tell me how can i decrease the hour,minute and seconds – lovejs Dec 15 '14 at 13:00
To decrease you should declare the c variable outside the scope of the function in the setInterval, and initialize it with the time you want in seconds, then in the setInterval, you set c = c - 1; (or c--; or c -= 1;) and you can display the result in your time format (see this link : http://stackoverflow.com/questions/6312993/javascript-seconds-to-time-string-with-format-hhmmss) – ykc Dec 15 '14 at 13:11

Make the clock decrement

What i need as my output

1 Answers1

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