Arrays

let colors
colors = ["red", "green", "blue", "orange"];
console.log(colors)

You can use another way to define arrays:

colors = new Array("red", "green", "blue", "yellow");
console.log(colors)

In javascript arrays an object like we saw the Date() object before. Arrays can hold mixed data types:

let mixVar = [45, "New York", true]
console.log(mixVar)

We can access specific item by array index, which starts from 0:

console.log(mixVar[1])

New York

Properties and methods of array (object)

Length of an array property:

console.log(colors.length);

4

Methods: reverse the array:

console.log(colors.reverse());

["yellow", "blue", "green", "red"] (4)

Remove the first item:

colors.shift();
console.log(colors);

["blue", "green", "red"] (3)

Add new items to the front of an array:

colors.unshift("purple", "orange");
console.log(colors);

["purple", "orange", "blue", "green", "red"] (5)

Remove the last item of an array:

let removedItem;
removedItem = colors.pop();  // in this way you can use the removed item
console.log(colors);


["purple", "orange", "blue", "green"] (4)

console.log(removedItem);

red

Add items to the end of the array:

colors.push("pink")
console.log(colors)

["purple", "orange", "blue", "green", "pink"] (5)

You can remove items from the middle of the array:

colors.splice(2, 1) // .splice(position, number of item to remove)
console.log(colors)

["purple", "orange", "green", "pink"] (4)

Copy an array using .slice()

let themeColors = colors.slice()
console.log(themeColors)

["purple", "orange", "green", "pink"] (4)

Index of

let pos = colors.indexOf("orange", 0); // give the position where to start the search, here 0.
console.log(pos);

1

Join the array elements:

let stringArray = colors.join();
console.log(stringArray)

purple,orange,green,pink

let stringArray = colors.join(", "); // you can give the separator as argument
console.log(stringArray)

purple, orange, green, pink

Properties and methods of array (object)​

Properties and methods of array (object)