looping through javascript array each time starting at new index

i have a javascript array like this:

 array = [
  {"Command": "SetDuration","QuestionId": "2","NewDuration": "1"},
  {"Command": "SetDuration","QuestionId": "2","NewDuration": "1"},
  {"Command": "SetDuration","QuestionId": "7","NewDuration": "7"},
  {"Command": "SetDuration","QuestionId": "6","NewDuration": "7"}
 ]

my task is loop through it 1 time in a minute, starting at increm开发者_如何学JAVAented index each time, so that after 3 minutes i would start from array[4] How to accomplish this? Thanks!

The magic of closures:

function createDwindlingLooper(arr) {
    var n = 0;
    return function() {
        for (var i = n; i < arr.length; i++) {
            console.log(i); // do real stuff here
        }
        n += 1; 
    }
}

var looper = createDwindlingLooper(array);

You can meet your timer requirement with this:

setInterval(createDwindlingLooper(array), 1000 * 60);

The value of n will be incremented by one each time looper is executed, achieving the desired effect:

var looper = createDwindlingLooper(array);
looper(); // 0, 1, 2, 3
looper(); // 1, 2, 3
looper(); // 2, 3
looper(); // 3
looper(); // 

When you set up your timer, you can do it from inside another function, and that function can maintain the index as a local variable.

function loopVerySlowly(array) {
  var index = 0;
  function doSomething() {
    //
    // do something with array[index] ...
    //
    index = (index + 1) % array.length; // increment for next time
  }

  return setInterval(doSomething, 1000 * 60);
}

var interval = loopVerySlowly(array);

That depends on how you want to performm the iteration. one way would be to call settimeout four times to run on different indices at minute increments, e.g.

for (var i=0 ; i<4 ; i++)
    settimeout(function(i){ return function(){
        // process here using i as index 
    }, 60000*i);

var checkme = {
    init: function(start) {
        for (var i = start; i < array.length; i++) {
            // alert(array[i].Command + ":" + array[i].QuestionId);
            //do what you want here
        };
        // start a new loop from current end
        if (array.length < start) {
            var t = setTimeout(checkme.init(start+1), 60000);//delay one minute
        };
    }
};
var t = setTimeout(checkme.init(0), 60000);//start first one in 1 minute

For a BIT more fun, use your "NewDuration" on the current (first) array element in each record so you can vary the amount of time delay by the data :)

NOT what you asked for exactly, but why not!

var checkme = {
    init: function(start) {
        for (var i = start; i < array.length; i++) {
            // alert(array[i].Command + ":" + array[i].QuestionId);
            //do what you want here
        };
        // start a new loop from current end
        var timedelay = array[start].NewDuration * 60000;
        // delay by NewDuration # minutes
        if (array.length < start) {
            var t = setTimeout(checkme.init(start+1), timedelay);
        };
    }
};
var t = setTimeout(checkme.init(0), 60000);//start first one in 1 minute