Count total of arrays in Javascript:

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[Object, Object, Object, Object]  
[Object, Object, Object, Object]  
[Object, Object, Object, Object]  
[Object, Object, Object, Object]  
[Object, Object, Object, Object]  
[Object, Object, Object, Object]

Has several arrays on a page and need to count them. Heed: I don’t want to use the length to find out how many items there are in each array and know how many arrays has the whole.

For example, in the list above I would return the number 6 (total of arrays).
I have a fixed test array: 

$scope.tickets = [{
    name: 'Pista Inteira - Lote 01',
    items: [{
      type: 'Homem',
      value: '100,00',
      quantity: 0
    }, {
      type: 'Mulher',
      value: '80,00',
      quantity: 0
    }]
  },
  {
    id: 1,
    name: 'Pista (PNE)',
    items: [{
      type: 'Homem',
      value: '100,00',
      quantity: 0
    }, {
      type: 'Mulher',
      value: '80,00',
      quantity: 0
    }]
  },
  {
    id: 2,
    name: 'Camarote',
    items: [{
      type: 'Homem',
      value: '100,00',
      quantity: 0
    }, {
      type: 'Mulher',
      value: '80,00',
      quantity: 0
    }]
  },
  {
    id: 3,
    name: 'Lounge',
    items: [{
      type: 'Homem',
      value: '100,00',
      quantity: 0
    }, {
      type: 'Mulher',
      value: '80,00',
      quantity: 0
    }]
  },
];

I run this array several times and would like to count how many times this array has been generated.

Can anyone tell me how to do it?

javascript angularjs

  • has the example of this set of arrays?

  • And where are these array on the page? Where do these come from array?

  • I’ll edit the question

  • 1

    you want the amount of arrays inside each key items?

  • 1

    How are these arrays generated? Anything encapsulates them in another array using push and take the length of it

  • I don’t see multiple arrays, I see an array of objects that contains array.

  • @Using no proposed solutions has served you?

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2 answers

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var app = angular.module("app", []);
app.controller("ctrl", ["$scope", function($scope) {
  $scope.count = 0;
  $scope.countItems = function()
  {
      $scope.count = 0;
      angular.forEach($scope.tickets, function(a){
         $scope.count += a.items.length;  
      });      
  }
  $scope.tickets = [{
      name: 'Pista Inteira - Lote 01',
      items: [{
        type: 'Homem',
        value: '100,00',
        quantity: 0
      }, {
        type: 'Mulher',
        value: '80,00',
        quantity: 0
      }]
    },
    {
      id: 1,
      name: 'Pista (PNE)',
      items: [{
        type: 'Homem',
        value: '100,00',
        quantity: 0
      }, {
        type: 'Mulher',
        value: '80,00',
        quantity: 0
      }]
    },
    {
      id: 2,
      name: 'Camarote',
      items: [{
        type: 'Homem',
        value: '100,00',
        quantity: 0
      }, {
        type: 'Mulher',
        value: '80,00',
        quantity: 0
      }]
    },
    {
      id: 3,
      name: 'Lounge',
      items: [{
        type: 'Homem',
        value: '100,00',
        quantity: 0
      }, {
        type: 'Mulher',
        value: '80,00',
        quantity: 0
      }]
    },
  ];
}]);
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="app" ng-controller="ctrl">
<button ng-click="countItems()">Clicar</button>
<div>{{count}}</div>
</div>

0

This solution below uses a recursive function and checks the properties of each object. If you pass primitive values in the for... in will give a stack overflow with strings (because at least in Ecmascript 5 there is getter to read each character, as to read each item of an array).

P.S.: here counted 5 of the total, and it appears to be.

// Quantidade de `Array`'s contadas.
var amount = 0;

function count(value) {
    var k;

    if (typeof value === 'object') {

        if (value instanceof Array) {
            // ou: value.constructor === Array
            ++amount;
        }

        for (k in value) {
            count(value[k]);
        }
    }
}

On the condition of checking if the value is an array... instanceof will work with classes that inherit Array.

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