Recall a function with the same parameters values with javascript

Question

I need to call a function with the same parameter's values to refresh a ChartJs with a new daterange.

The _reportDateStart and _reportDateEnd are updated outside of the function, so I need to recall the function so the chart is updated with the new data.

The script is:

var _reportDateStart;
var _reportDateEnd;

var _loadChart = function (chartLabel, queryMetrics, queryDimensions) {}

The call is made like this:

_loadChart("Visits", "ga:sessions", "ga:date,ga:nthDay");

But can also be:

 _loadChart("Users", "ga:users", "ga:date,ga:nthDay");

Is there something preventing you from just passing the same arguments again? — Niet the Dark Absol, Mar 20 '17 at 17:23
Hi, thanks! Yes, I was just updating the question with this. — Patrick, Mar 20 '17 at 17:24
Your update doesn't explain why you can't use the same arguments. — Nick is tired, Mar 20 '17 at 17:26

score 2 · Answer 1 · answered Mar 20 '17 at 17:25

2

Declare globally accessible variables and assign the parameters on every call that way you can call the function with those variables again: Example:

var param1,param2,param3;
var _loadChart = function(a, b, c){
    param1 = a;
    param2 = b;
    param3 = c;
    //rest of the code.
};

function callTheFunctionAgain(){
    _loadChart(a, b, c);
}
_loadChart("Visits", "ga:sessions", "ga:date,ga:nthDay");
callTheFunctionAgain();

answered Mar 20 '17 at 17:25

Shakti Phartiyal

6,156
3
25
46

Hi thanks! Is there a way to just call _loadChart again without setting the parameters outside of the function? – Patrick Mar 20 '17 at 17:27
No I don't think so, you need to store the parameters somewhere if you plan to call the function with those parameters again. If you are planning to call the function from within itself again, then in that case no need to store the variables anywhere simply call _loadChart(chartLabel, queryMetrics, queryDimensions); But that is applicable only if you call it from within itself. – Shakti Phartiyal Mar 20 '17 at 17:29

score 1 · Answer 2 · answered Mar 20 '17 at 17:30

1

to do this you can create a new function with bound param as you wish like this var _loadChartBounded = _loadChart.bind(null, "Visits", "ga:sessions", "ga:date,ga:nthDay")

then every time you call _loadChartBounded() it will get the same param

answered Mar 20 '17 at 17:30

Nguyễn Hòang

11
1
2

Hi thanks! And how do you declare the original function _loadChart ? – Patrick Mar 20 '17 at 17:32
just do the same way you did in your code, my code extend from it – Nguyễn Hòang Mar 20 '17 at 17:35
yes, im sure it work every where, because it is build-in feature of javascript , in Function.prototype.bind https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind – Nguyễn Hòang Mar 20 '17 at 17:38
>= IE9 maybe an issue – Patrick Mar 20 '17 at 17:41
if you must support IE9 or lower just add polyfill in my link to mdn – Nguyễn Hòang Mar 20 '17 at 17:46
I have 2 questions after testing your code, why null in the first parameter? And in my case I have to define the bind and call it right after, correct? when I want to create the chart in the first time – Patrick Mar 21 '17 at 19:42

score 0 · Answer 3 · edited May 23 '17 at 12:09

0

We already have global variables and .bind()
I will throw in another solution which uses a closure

For an explanation on how these work, head over to this question and its excellent answers:
How do JavaScript closures work?

// This is only an example.
// Please change the variable names to something more meaningful :)

var _loadContent = (function() {
  var _a, _b, _c;

  return function(a, b, c) {
    if (typeof _a === "undefined") {
      _a = a;
      _b = b;
      _c = c;
    }

    console.log(_a, _b, _c);
  }
}());

_loadContent(1, 2, 3);
_loadContent(4, 5, 6);
_loadContent();

edited May 23 '17 at 12:09

Community

1
1

answered Mar 20 '17 at 17:47

Andreas

21,535
7
47
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Hi thanks! The bind solution seems more simple to implement – Patrick Mar 20 '17 at 17:56
I've added it because of your _">= IE9"_ comment. This would also work with IE6 – Andreas Mar 20 '17 at 17:58

score 0 · Answer 4 · answered Jun 16 '20 at 00:53

For those arriving in the now (15 Jun 2020), here's the most robust way to call a function from within it:

let fn = (a, b, c) => {
    /* fn's content */
    fn(...arguments);
}

This works great if you don't know what the parameters will be (user input), or simply do not want to have to change the parameters in multiple places when refactoring the code.

Reference

Recall a function with the same parameters values with javascript

4 Answers4