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JavaScript How to define an array of undefined length of empty objects?

rated 0 times [ 33] [ 2] / answers: 1 / hits: 5936 / 11 Years ago, sun, february 2, 2014, 12:00:00

var array = [];



var object = {};

Now, I need an array of empty objects.

array[0] = {};

array[1] = {};

//........

//........

and

var array = [{}];

is obviously not right.

How to define array of (empty) objects in JS?

var array = [{},{},{},{},.........];

Thanks.

EDIT:

The reason I need is the same reason that having an array with undefined length is useful, and mathematically natural in some cases.

I need object wrappers, and for initialization, it's just an empty object, like some values are null or undefined in many cases.

so, I'll have

var object = {};

array[0].value = 'foo', array[1].value = 'bar'.....

However, I do need multiple object wrappers, and the number is not pre-determined, so consequently, I need an arrays of the objects.

So, I am sorry, I modify my Question title

JavaScript How to define an array of undefined length of empty objects?

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megb

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1 Year ago

answered 11 Years ago sidneyh · Accepted Answer

Arrays can grow and shrink dynamically. So from a certain point of view, they are already of undefined length. You can always add new objects to it if you want to.

You can also create a helper function which checks first if an object exists at a certain position and if not, creates a new one.

You mentioned array[2].value = 'foo' as an example. Here is a helper function that you could use:

function getObjectAtIndex(arr, index) {

    return arr[index] || (arr[index] = {});

}

and then, instead of writing array[2].value = 'foo', you'd write:

getObjectAtIndex(array, 2).value = 'foo'