Clash Royale CLAN TAG

AngularJS compare two (scope) arrays and only POST the 'non-same' result (2018)

I have two arrays that i like to compare on the ID, if the ID from one array does not exist in the other i will add it with the Http Post.

This is the build up:

$scope.Games = [{id:1,Name:"BatMan"},
{id:2,Name:"SpiderMan"},
{id:2,Name:"Hulk"}];

$scope.NewGames = [{id:1,Name:"BatMan"},
{id:2,Name:"SpiderMan"},
{id:3,Name:"Hulk"},
{id:4,Name:"DeadPool"},
{id:5,Name:"IronMan"}, ,
{id:6,Name:"DrStrange"}];


so i load all the Games and NewGames with a GET in the two $scopes
Now i would like to compare the two on the id_game, so i was thinking of something like this but can't get it to work, the http section works find however without the indexOf, it will add all the games double in DB if they already existed and that is what i want to prevent.

angular.forEach($scope.NewGames, function (value, index) {

if ($scope.Games.indexOf(value.id ) === -1) {

console.log('New game to add' + value.Name)

$http({
method: 'POST',
url: 'http.....addGame',
data: value
})
}
})


1 Answer
1

Since $scope.Games is an array of Objects use findIndex() instead of indexOf().

$scope.Games

findIndex()

indexOf()

The findIndex() method executes the function once for each element present in the array:

findIndex()

If it finds an array element where the function returns a true value, findIndex() returns the index of that array element (and does not check the remaining values). If no such element is found it returns -1. In the example given below:

o is each object/element of array games and we check for equality between the id(o.id) prop for each object of games array with the findId. If there is an element in the games array, where the id matches with the findId, the condition turns true and findIndex returns the index of that element/object.

o

games

id

games

findId

findId

findIndex

var games = [{id:1,value:"abc"},{id:2,value:"dfg"},{id:2,value:"fdf"}];
var findId = 2;
// when object with id is present in array
if(games.findIndex((o)=>o.id == findId) > -1);
console.log("Found");
findId= 6;
//when object with id is not present in array
if(games.findIndex((o)=>o.id == findId) == -1);
console.log("Not found");

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