Is there a way to call a function through using a string that matches its name?

Question

This is what I have attempted, and may give a better gist of the question I'm trying to ask:

var x = "run";
var y = "Function";
var xy = x + y;

function runFunction() {
    console.log("Function has been called.");
}

xy();

What am I doing wrong here?

you're basically doing this `'runFunction'()` And that's not how you call a function. — Kevin.a, Dec 17 '20 at 09:57
In practice, you never need — or _want_, really — dynamic variable names. Use a simple object instead: `const obj = { runFunction(){`…`} };` … `obj[x + y]();`. — Sebastian Simon, Dec 17 '20 at 09:59

score 1 · Accepted Answer · answered Dec 17 '20 at 09:58

1

You could use eval(), but don't. Instead, store your functions in an object:

const functions = {
  greetingOne: () => console.log("Hello!"),
  anotherGreeting: () => console.log("Hi there!");
};

const f = "greetingOne";
functions[f]();

answered Dec 17 '20 at 09:58

AKX

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Thank you, this solved my problem :) – mennobrandt Dec 17 '20 at 11:09

score 0 · Answer 2 · edited Dec 17 '20 at 09:59

0

It is possible if the function lives on an object.

const obj = {
  runFunction: function() {console.log('hello')}
}

var x = "run";
var y = "Function";
var xy = x + y;

obj[xy]();

edited Dec 17 '20 at 09:59

Sebastian Simon

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answered Dec 17 '20 at 09:58

enno.void

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score 0 · Answer 3 · answered Dec 17 '20 at 10:03

0

You can call eval that run string as Javascript code

function runFunction() {
    console.log("Function has been called.");
}
functionName = 'runFunction'
eval(functionName + '()');

answered Dec 17 '20 at 10:03

jacob galam

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score 0 · Answer 4 · answered Dec 17 '20 at 10:03

0

All global functions stores in window object.

let first = "first";
let second = "Second";

let xy = first+second;

function firstSecond() {
    return "Hello World";
}


console.log(window[xy]());

answered Dec 17 '20 at 10:03

sourav satyam

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this is only valid for javascript in a browser – enno.void Dec 17 '20 at 10:59

Is there a way to call a function through using a string that matches its name?

4 Answers4