How to grab array of string represented parameters in JavaScript

Question

I'm trying to grab an array of string represented parameters from a function and I'm unsure how to proceed. Basically given the function below

function MyFunc(param1, param2, param3){
  //do all the things
}

What would the function "getParams" look like to do the following

getParams(MyFunc) // ["param1","param2","param3"]

What are you trying to achieve? The best you can do is convert the function to a string and then extract the parameters by some sort of simple parse. — Pointy, Mar 28 '16 at 14:02
I'm trying to achieve automated dependency injection in angular. So for example if I have a controller function MyCtrl($scope){} I can do `MyCtrl.$inject = getParams(MyCtrl);` — frostme, Mar 28 '16 at 14:04

millerbr · Answer 1 · 2016-03-28T14:21:05.177

0

This is a bit messy, but you can do this by converting your function to a string and then splitting it until you get just the parameters:

var getFuncParams = function(MyFunc) {
    var str = MyFunc.toString()
    var strParams = str.substr((str.indexOf('(')+1), (str.indexOf(')') - str.indexOf('(')) - 1)
    var params = strParams.split(",")
    return params;
}

edited Mar 28 '16 at 14:21

answered Mar 28 '16 at 14:12

millerbr

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this seems to accomplish exactly what I was trying to do thanks! – frostme Mar 28 '16 at 14:19
No problem - I've edited it slightly to be inside it's own function. Hope it helps! – millerbr Mar 28 '16 at 14:23

How to grab array of string represented parameters in JavaScript

1 Answers1