JavaScript - Checking for an Array inside an Array of Arrays

Question

I have an array that is made of three arrays.

I have a value (an array, '[7,5]') that I want to check through the arrays for.

https://jsfiddle.net/qx4wLf4f/6/

var arrays = [];
var arrayOne = [ [1,3], [2,3], [2,4] ];
var arrayTwo = [ [7,6], [7,5], [7,4] ];
var arrayThree = [ [3,3], [3,2], [2,2] ];
arrays.push( arrayOne, arrayTwo, arrayThree );

function checkArraysForValue( val ){
    if( !$.isArray(val) ){
    $('#result').html('Not Array');
    return false;
  }
  var found = 'not found';
  arrays.forEach(function( item, index ){
    if( item.indexOf( val ) > -1 ){
        found = 'did find';
    }
  });
  $('#result').html(found);
}


checkArraysForValue( [7,5] );

Answer 1

For your specific scenario, just JSON.stringify and indexOf will do

var isPresent = JSON.stringify( arrays ).indexOf( JSON.stringify( val ) ) != -1;

Demo

 var arrays = []; var arrayOne = [ [1,3], [2,3], [2,4] ]; var arrayTwo = [ [7,6], [7,5], [7,4] ]; var arrayThree = [ [3,3], [3,2], [2,2] ]; arrays.push( arrayOne, arrayTwo, arrayThree ); function checkArraysForValue( val ) { //console.log( JSON.stringify( arrays ) ); //console.log( JSON.stringify( val ) ); return JSON.stringify( arrays ).indexOf( JSON.stringify( val ) ) != -1 ? "Found" : "Not Found"; } console.log(checkArraysForValue( [7,5] )); 

Answer 2

function isArrayIdentical(arr1, arr2){
    if(arr1.length !== arr2.length)
    return false;
  for(var i = arr1.length; i--;){
    if(arr1[i] !== arr2[i])
        return false;
  }
  return true;
}

this is the function which you need to work with, i have included a fiddle for the implemented solution to your question below. https://jsfiddle.net/2r4y9mr9/

basically, you can also stringify your sample for performing string matching in the answer but then, solution will not be correct if "1" and 1 is different in your consideration.

Answer 3

array.forEach()

doesn't work like you think. Here my jsFiddle to exaplain what this method does. I solved your problem with this but it's not efficient.

var arrays = [];

var arrayOne = [
  [1, 3],
  [2, 3],
  [2, 4]
];
var arrayTwo = [
  [7, 6],
  [7, 5],
  [7, 4]
];
var arrayThree = [
  [3, 3],
  [3, 2],
  [2, 2]
];
arrays.push(arrayOne, arrayTwo, arrayThree);

function isEqual(arr1, arr2) {
  if (arr1.length !== arr2.length)
    return false;
  for (var i = arr1.length; i--;) {
    if (arr1[i] !== arr2[i])
      return false;
  }
  return true;
}

function checkArraysForValue(val) {
  if (!$.isArray(val)) {
    $('#result').html('Not Array');
    return false;
  }
  var val = val;
  var found = 'not found';
  for(var i = 0; i < arrays.length; i++){
    for(var j = 0; j < arrays[i].length; j++){
        if(isEqual(arrays[i][j],val)){
        found = 'did found';
      }
    }
  }
  $('#result').html(found);
}