An iterative approach to arrays

One, every (), runs the given function for each item in the array, and returns True if the function returns true for each item.

var arr=[1,2,3,4,5,6,7,8,9];everyresult=arr.every (function(item,index,array) {     return (item>2);    

The result of execution is false;

var arr=[1,2,3,4,5,6,7,8,9];arr.foreach (function(item,index,array) {     // perform certain Actions })

Two, filter (); Each item in an array runs the given function, and returns the list of items that the function returns True.

var Arr=[1,2,3,4,5,6,7,8,9];var filterresult=arr.filter (function (item,index,array) {    return (item>2);}) Alert (Filterresult ());

Returns an array and each value in the array is greater than 2 [3,4,5,6,7,8,9];

Three, ForEach (); Runs the given function for each item in the array, and the method does not return a value; it is essentially the same as using a for loop to iterate over an algebraic group.

var arr=[1,2,3,4,5,6,7];arr.foreach (function(item,index,array) {    //  perform certain Actions })

Four, map, an array of each of the arrays that run the given function, nearly returning the result of each function call.

var arr=[1,2,3,4,5,6,7]; var mapresult=arr.map (function(item,index,array) {    return item*2;}); Alert (Mapresult)

The value returned is; [2,3,6,8,10,12,14];

Five, some, runs the given function for each item in the array, and returns True if the function returns true for either item.

var arr=[1,2,3,4,5,6,7]; var someresult=arr.some (function(item,index,array) {    return ( Item>2);}); alert (someresult);

The returned result is true;

Iterative methods for arrays