javascript / jQuery - match a function from array of function

Question

so I have a array of functions like this one:

var functions = [
   func1 = function(){ ... },
   func2 = function(){ ... },
   func3 = function(){ ... }
] ;

If I call a function like functions[func1]() it works, but if I call it like functions['func1']() it doesn't.

What's the difference?

And how can I call a function using the 2nd method (match the function name with a string)?

Alnitak · Accepted Answer · 2011-04-28 13:22:09Z

4

It needs to be an object containing keys:

var functions = {
   func1: function(){ ... },
   func2: function(){ ... },
   func3: function(){ ... }
};

This will allow functions['func1']() to work.

I don't know how your functions[func1]() ever worked, though.

Your original code would have (inadvertently) created global variables (func1, etc) but those wouldn't have been valid indices into the functions array.

answered Apr 28, 2011 at 13:22

Alnitak

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4 Comments

Alex Over a year ago

can I still use array like indexes on it? like functions[5] or functions[functions.length] etc?

Alnitak Over a year ago

Only if you also do something like: functions[0] = functions.func1 for each element. NB: array offsets start at zero.

Alex Over a year ago

but there are too many, I don't want to make the code so big :( Is there any way I could randomly pick a function from that object? (this is why I asked about the indexes)

Alnitak Over a year ago

Sure, pick a random number as an offset into the array returned by Object.getOwnPropertyNames(functions)

Mottie · Accepted Answer · 2011-04-28 13:42:14Z

4

If you want to call a random function, try something like this (demo):

var functions = [
   [ function(el){ el.html('function 1'); } ],
   [ function(el){ el.html('function 2'); } ],
   [ function(el){ el.html('function 3'); } ]
],

    random = Math.round(Math.random() * functions.length),
    output = $('#display');

functions[random][0](output);

answered Apr 28, 2011 at 13:42

Mottie

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2 Comments

js1568 Over a year ago

Why are you nesting all the functions in arrays?

Mottie Over a year ago

@js1568: Because in the follow up comments, Alex asked if it was possible to pick a function using a random index.

Bastardo · Accepted Answer · 2011-04-28 13:24:38Z

1

var functions = {   
                func1: function(){ ... },   
                func2: function(){ ... },   
                func3: function(){ ... }
};

answered Apr 28, 2011 at 13:24

Bastardo

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