Javascript closure and setTImeInterval function

Question

<!DOCTYPE html>
<html>
<body>

<script>
function sampleDelay(delay) {
  return function(functionArray) {
    var count = 0;
    var func = setInterval(function(){
    if(count === functionArray.length){
      clearInterval(func);  
    }
          count++;
    console.log(functionArray[count-1]);
      return functionArray[count-1];        
    }, delay);

  };
}


var DelayedValue = sampleDelay(1000)([
  1,2,3,4,5
]);
</script>

</body>
</html>

I want to get the values of DelayedValue varibale to be 1,2,3,4,5 after a delay of one second. This code is not returning values of DelayedValue variable.

Please suggest what i am doing wrong ?

Answer 1

This is because you made your code asynchronous by introducing the interval. Your function already finished executing while the interval is still running. You need to work with callbacks and/or promises to solve this.

You can do it like this for example ( fiddle ):

function delayedOutput(values, delay, callback){
    var step = 0,
        interval = setInterval(function(){
            callback(values[step++]);

            if(step === values.length){
                clearInterval(interval);
            }
    }, delay); 
}

delayedOutput([1,2,3,4,5], 1000, function(i){
    document.getElementById('output').innerHTML += i;
});

Javascript closure and setTImeInterval function

Question

1 answers

solution1
1 ACCPTED 2013-11-06 10:29:14

Javascript closure and setTImeInterval function

Question

1 answers

solution1 1 ACCPTED 2013-11-06 10:29:14

solution1
1 ACCPTED 2013-11-06 10:29:14