Arrays


JavaScript can hold an array of variables in an Array object. In JavaScript, an array also functions as a list, a stack or a queue.

To define an array, either use the brackets notation or the Array object notation:

var myArray = [1, 2, 3];
var theSameArray = new Array(1, 2, 3);

Addressing

We can use the brackets [] operator to address a specific cell in our array. Addressing uses zero-based indices, so for example, in myArray the 2nd member can be addressed with index 1.

console.log(myArray[1]);      // prints out 2

Arrays in JavaScript are sparse, meaning that we can also assign variables to random locations even though previous cells were undefined. For example:

var myArray = []
myArray[3] = "hello"
console.log(myArray);

Will print out:

[undefined × 3, "hello"]

Exercise

You must define an array with the following three variables:

  1. A string which has the value of "What is the meaning of life?"
  2. A number which has a value of 42
  3. A boolean which has a value of true

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