Jacob Johns Basic Data Structures Lesson

Arrays to Store a Collection of Data

arrays can contain booleans, strings, and numbers, among other valid JS data types

Access Array's Contents Using Bracket Notation

the fundamental feature of any data structure is the ability to retrieve data as well as store

Add Items to an Array

push() and unshift() giveth

Remove Items from an Array

pop() and shift() taketh away

Remove Items Using splice()

remove any number of consecutive elements from anywhere in an array

Adding Items Using splice()

the third parameter can be used to add to the array

Copy Array Items Using slice()

extract a given number of elements to a new array, leaving the array it is called upon untouched

Copy Array with Spread Operator

ES6's new spread operator easily copies all of an array's elements

Combine Arrays with Spread Operator

combine arrays, or insert elements of one array into another, at any index

Check for Presence of Element with indexOf()

allows a quick and easy check for the presence of an element on an array

							//create function to check true or false if elem exists on the provided array

							//my solution
							function quickCheck(arr, elem) {
								let checkIndex = arr.indexOf(elem);
								if (checkIndex >= 0) {
									return true;
								} else {
									return false;
								}
							}

							//provided array
							console.log(quickCheck(['squash', 'onions', 'shallots'], 'mushrooms'));

							//review solutions

							//first solution is similar to mine but less work
							function quickCheck(arr, elem) {
								if (arr.indexOf(elem) >= 0) {
									return true;
								}
								return false;
							}

							function quickCheck(arr, elem) {
								return arr.indexOf(elem) >= 0 ? true : false;  //this is the way I should have went...
							}

							function quickCheck(arr, elem) {
								return arr.indexOf(elem) != -1; //this one is even better
							}

Iterate Through All an Array's Items using For Loops

it is very handy to be able to iterate through each item to find one or more elements