Array Method Cheat Sheet
by trentHarlem
JavaScript
//let empty = []
// to MUTATE the original array
// Add to original
let array = ['original','array']
console.log(array)
array.push('push to end')
console.log('push',array)
array.unshift('unshift to start')
console.log('unshift',array)
// Remove from original
array.pop()// removes last item
console.log('pop',array)
array.shift()//removes first item
console.log('shift',array)
array.splice() // add and or remove to specified index
//array.reverse()// reverses order of items
//array.sort()// sort defined by function. default sort is alphabetical
const empty = new Array(5)
empty.fill(1)// fills empty array created with new Array
console.log('fill new Array', empty)
empty.splice(2,0,'splice')
// mute the other splices and logs to view the individual changes
console.log('splice 2,1',empty, 'splice at index 2 and replace 1 index')
//empty.splice(-1,0,'splice')
//console.log('splice 2,0',empty)
//empty.splice(0,5,'splice')
//console.log('splice 0,5',empty)
//console.log(array)
let test = ['poo']
function insert(arr,index_Number,...items_Nums_or_Strings){
//console.log(arr.splice(index_Number,0,...items_Nums_or_Strings))
//console.log(arr)
return arr.splice(index_Number,0,...items_Nums_or_Strings)
}
insert(test,0,'poop')
insert(empty,0,'poop')
console.log(test.splice(0,0,'foo', 'fighters'))
console.log(test)
console.log(empty.filter(item=>typeof(item)==='number'))
console.log(empty.filter(item=>typeof(item)==='string'))
console.log(empty)