I have the following :
$scope.Items = [{"ItemId": 1, "ItemName":"Test1"}, {"ItemId": 2, "ItemName":"Test2"}, {"ItemId": 3, "ItemName":"Test3"}];
If I wish to check if ItemId 1 AND ItemId 2 exist within this, what would be the best approach for it? I believe the indexOf property should work, but how can it be used to check if a particular attribute value of the object exists within the array?
you can use like also
$scope.firstitem=false;
$scope.seconditem=false;
angular.forEach($scope.Items, function (value, key) {
if (value.ItemId== 1) { $scope.firstitem=true; }
if (value.ItemId== 2) { $scope.seconditem=true; }
});
You could use find function like this to find by property you want.
var inventory = [
{name: 'apples', quantity: 2},
{name: 'bananas', quantity: 0},
{name: 'cherries', quantity: 5}
];
function findCherries(fruit) {
return fruit.name === 'cherries';
}
console.log(inventory.find(findCherries));
// { name: 'cherries', quantity: 5 }
If you wish to filter (i.e , find multiple values.) you can use the filter function like this:
var arr = [
{ id: 15 },
{ id: -1 },
{ id: 0 },
{ id: 3 },
{ id: 12.2 },
{ },
{ id: null },
{ id: NaN },
{ id: 'undefined' }
];
var invalidEntries = 0;
function filterByID(obj) {
if (obj.id !== undefined && typeof(obj.id) === 'number' && !isNaN(obj.id)) {
return true;
} else {
invalidEntries++;
return false;
}
}
var arrByID = arr.filter(filterByID);
console.log('Filtered Array\n', arrByID);
// Filtered Array
// [{ id: 15 }, { id: -1 }, { id: 0 }, { id: 3 }, { id: 12.2 }]
console.log('Number of Invalid Entries = ', invalidEntries);
// Number of Invalid Entries = 4
Ref : https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/filter
You could use lodash's _.some() operator
var _ = require('lodash');
var Items = [{"ItemId": 1, "ItemName":"Test1"}, {"ItemId": 2, "ItemName":"Test2"}, {"ItemId": 3, "ItemName":"Test3"}];
var hasItem1 = _.some(Items, ["ItemId", 1]);
var hasItem2 = _.some(Items, ["ItemId", 2]);
console.log ("hasItem1 = "+hasItem1);
console.log ("hasItem2 = "+hasItem2);
You could use lodash's _.findIndex() operator
var _ = require('lodash');
var Items = [{"ItemId": 1, "ItemName":"Test1"}, {"ItemId": 2, "ItemName":"Test2"}, {"ItemId": 3, "ItemName":"Test3"}];
var hasItem1 = false;
var hasItem2 = false;
if(_.findIndex(Items, {ItemId : 1}) != -1) { hasItem1 = true; }
if(_.findIndex(Items, {ItemId : 2}) != -1) { hasItem2 = true; }
console.log ("hasItem1 = "+hasItem1);
console.log ("hasItem2 = "+hasItem2);
Array.find: developer.mozilla.org/en/docs/Web/JavaScript/Reference/…