JavaScript For Loop executes for last value of iterator only

Question

I am trying to download files from some website say 'website.com'. I have all the unique ids in an array.

This is the code that I have written:

for(var i=0;i<ids.length;i++) {
    var timeInterval = 1000;
    (function(i,timeInterval){
        setTimeout(function(){
            var link = document.createElement('a');
            link.href= "http://website.com/download/"+ids[i];
            var e = document.createEvent('MouseEvents');
            e.initEvent('click', true, true);
            link.dispatchEvent(e);
            console.log(ids[i]);
            console.log(timeInterval);
        }, timeInterval);
        timeInterval = (i+1)*1000;
    })(i,timeInterval);
}

Problem with this is that it downloads the file corresponding to the last element of the array ids, not all of them.
How can I make the loop work for each and every element in ids?
PS: I have tried out various solutions given in different related questions, but none could bring desired results, so I had to post it as a different question.

Answer 1

You're updating the "timeInterval" parameter at the end of the anonymous function, and while there's nothing wrong with that statement it doesn't do any good — it updates the "timeInterval" parameter, not the "timeInterval" variable outside the loop. You could do this as one alternative:

for(var i=0;i<ids.length;i++) {
    var timeInterval = (i + 1) * 1000;
    (function(i,timeInterval){
        setTimeout(function(){
            var link = document.createElement('a');
            link.href= "http://website.com/download/"+ids[i];
            var e = document.createEvent('MouseEvents');
            e.initEvent('click', true, true);
            link.dispatchEvent(e);
            console.log(ids[i]);
            console.log(timeInterval);
        }, timeInterval);
    })(i,timeInterval);
}

to just do the computation outside the anonymous function.

edit — note that you may still run into problems, depending on the context in which this code runs. Browsers might not like this behavior.