CODEWITHSUNDEEP
javascriptarrays
Dimitri
Dimitri

Reputation: 1966

Pushing functions into an Array in Javascript

Is there a way to push a list of functions into an associative array? Here's what I'm trying to do:

var inits = {
    "first"  : fn1(),
    "second" : fn2(),
    "third"  : fn3(),
    "fourth" : fn4()

};

var functions = ['first','fourth'];

for(var index in functions ) {

    inits[functions[index]];

}

The important part here is to be able to name each function and have it called based on a given array of function names. I can do this in PHP but can't figure it out how to do it in javascript.

Upvotes: 0

Views: 110

Answers (2)

svidgen
svidgen

Reputation: 14282

Just a few small changes should make it work:

var inits = {
    "first"  : function() { /* make sure there's a function body */ },

    "second" : fn2,   // or this, if you intend to call a function named `fn2`
                      // or assigned to a locally accessible fn2 variable.

    "third"  : fn3(), // or this, if fn3() returns a function ...
    "fourth" : fn4(), // but, this version *probably* isn't what you want.

};

var functions = ['first','fourth'];

// generally speaking, don't use for-in on an array.
for(var i = 0; i < functions.length; i++) {

    // use parentheses to invoke the function
    inits[functions[i]]();

}

Upvotes: 1

user229044
user229044

Reputation: 239270

First, you're not actually storing functions. You're storing the return value of functions.

To store the function, you'd use 

var inits = {
  'first': fn1,
  'second': fn2,
   ...
};

Secondly, you're iterating incorrectly over the array.

Use forEach:

functions = ['first', 'fourth'];

functions.forEach(function (fn) {
    inits[fn];
});

Thirdly, in your loop, you don't actually try to invoke the function. If that's your intent, you're missing a (): 

functions.forEach(function (fn) {
    inits[fn]();
});

Upvotes: 2

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