Comparing and Filtering two arrays

You can use filter as follow

var array1 = ['apples', 'grapes', 'oranges', 'banana'],  array2 = ['potato', 'pears', 'grapes', 'berries', 'apples', 'oranges'];var intersection = array1.filter(function(e) {  return array2.indexOf(e) > -1;});console.log(intersection);

You can also add this method on Array prototype and call it directly on array

Array.prototype.intersection = function(arr) {  return this.filter(function(e) {    return arr.indexOf(e) > -1;  });};var array1 = ['apples', 'grapes', 'oranges', 'banana'],  array2 = ['potato', 'pears', 'grapes', 'berries', 'apples', 'oranges'];var intersection = array1.intersection(array2);console.log(intersection);

Hi this is a porting of the function array_intersect php. Should be good for youhttp://phpjs.org/functions/array_intersect/

function array_intersect(arr1) {  //  discuss at: http://phpjs.org/functions/array_intersect/  // original by: Brett Zamir (http://brett-zamir.me)  //        note: These only output associative arrays (would need to be  //        note: all numeric and counting from zero to be numeric)  //   example 1: $array1 = {'a' : 'green', 0:'red', 1: 'blue'};  //   example 1: $array2 = {'b' : 'green', 0:'yellow', 1:'red'};  //   example 1: $array3 = ['green', 'red'];  //   example 1: $result = array_intersect($array1, $array2, $array3);  //   returns 1: {0: 'red', a: 'green'}  var retArr = {},    argl = arguments.length,    arglm1 = argl - 1,    k1 = '',    arr = {},    i = 0,    k = '';  arr1keys: for (k1 in arr1) {    arrs: for (i = 1; i < argl; i++) {      arr = arguments[i];      for (k in arr) {        if (arr[k] === arr1[k1]) {          if (i === arglm1) {            retArr[k1] = arr1[k1];          }          // If the innermost loop always leads at least once to an equal value, continue the loop until done          continue arrs;        }      }      // If it reaches here, it wasn't found in at least one array, so try next value      continue arr1keys;    }  }  return retArr;}

Here is one simple way based on your code

function array_filter(filter, result) {    var filterLen = filter.length;    var resultLen = result.length;    for (i = 0; i < resultLen; i++) {        for (j = 0; j < filterLen; j++) {            if (!contains(filter, result[i]))                result.splice(i, 1);        }    }}//Return boolean depending if array 'a' contains item 'obj'function contains(array, value) {    for (var i = 0; i < array.length; i++) {        if (array[i] == value) {            return true;        }    }    return false;}