JavaScript_Succinctly

Chapter 15 Array()
Conceptual overview of using Array() objects
An array is an ordered list of values typically created with the intention of looping
through numerically indexed values, beginning with the index zero. What you need to
know is that arrays are numerically ordered sets, as opposed to objects which have
property names associated with values in non-numeric order. Essentially, arrays use
numbers as a lookup key, while objects have user-defined property names. JavaScript
does not have true associative arrays, but objects can be used to achieve the
functionality of associative arrays.
In the following sample, I store four strings in myArray that I can access using a
numeric index. I compare and contrast myArray to an object literal mimicking an
associative array.
Sample: sample133.html
var myArray = ['blue', 'green', 'orange', 'red'];
console.log(myArray[0]); // Logs blue using the 0 index to access the
string in myArray.
// Versus
var myObject = { // aka an associative array/hash, known as an object in
JavaScript.
'blue': 'blue',
'green': 'green',
'orange': 'orange',
'red': 'red'
};
console.log(myObject['blue']); // Logs blue.
Notes
Arrays can hold any type of values, and these values can be updated or deleted at any
time.
If you need a hash (aka associative array), an object is the closest solution.
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