add values of array javascript code example

Example 1: javascript insert item into array

var colors=["red","blue"];
var index=1;

//insert "white" at index 1
colors.splice(index, 0, "white");   //colors =  ["red", "white", "blue"]

Example 2: javascript append to array

var colors=["red","white"];
colors.push("blue");//append 'blue' to colors

Example 3: sum of all numbers in an array javascript

const arrSum = arr => arr.reduce((a,b) => a + b, 0)

Example 4: javascript array push

let animals = ["dog","cat","tiger"];

animals.pop(); // ["dog","cat"]

animals.push("elephant"); // ["dog","cat","elephant"]

Example 5: javascript append to array

arr = [1, 2, 3, 4]
arr.push(5) // adds element to end

arr.unshift(0) // adds element to beginning