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In a web page that uses javascript I need to maximize the speed with which it is filled
an array (myArray).
The way I will use to do this is summarized with the following example, which fills an Array of integers
called Array1:
1) The usual way to enter elements in Array1 is:
var Array1 = [5,7];
Array1.push (10);
2) But if I know a priori the size I will need for the Array, it is much faster to do so:
var Array1 = [0, 0, 0, 0, 0]; // Allocated array of length 5.
var A1Length = 0;
// to do a ‘push’, do
Array1 [A1Length ++] = 10;
However, the Array that I am using on my website (myArray) does not contain integers, but objects
each of which is an Array of two elements.
It is not a two-dimensional Array, but an array that contains Array objects.
I will use it as a map where “A” is the key and “B” is the value that I am looking for.
Currently, I fill it like this and it works correctly:
var myArray = [];
var newElement = {“A”: 10, “B”: ‘Name 1’}
myArray.push (newElement);
To increase the speed with which myArray is filled, following the example discussed for Array1,
I need to declare it with the size it will have (1000 Array objects of two dimensions).
I have tried to declare it like this:
var myArray = Array.from (Array (1000), () => new Array (2));
var myArrayUsed = 0;
And then insert new elements in it:
var newElement = {“A”: 10, “B”: ‘Name 1’}
myArray [myArrayUsed ++] = newElement;
The problem is that this code does not work and I think it is because myArray declaration statement
is not correct.