I have have been working with AngularJS. I have a JSON file of which each object needs to be displayed in a new partial. There are 100 objects in the JSON file, I need to randomly choose three. How do I achieve this?
the controller:
myApp.controller('DetailsController', ['$scope', '$http','$routeParams' ,function($scope, $http, $routeParams) {
$http.get('js/JOSCO.json').success(function(data) {
$scope.questions = data; // Array of 100 objs
console.log($scope.questions);
$scope.whichItem = $routeParams.itemId; // I want to assign 3 random numbers to whichItem
if($routeParams.itemId > 0){
$scope.prevItem = Number($routeParams.itemId) - 1;
}
else{
$scope.prevItem = $scope.questions.length - 1;
}
if($routeParams.itemId < $scope.questions.length-1){
$scope.nextItem = Number($routeParams.itemId) + 1;
}
else{
$scope.nextItem = 0;
}
});
}]);
Currently it is taking in all 100 items...
To access a random item in your array you can use.
$scope.randomItem = data[Math.floor(Math.random() * data.length)];
If you repeat it three times then you get the three random elements. Still you could create a function to make the code DRY.
function getRandomItem(items) {
return items[Math.floor(Math.random() * items.length)];
}
The solution above could get the same item multiple times if it is called three times. You could use splice() to remove the item from the original array.
function getRandomItem(items) {
var randomIndex = Math.floor(Math.random() * items.length);
var item = items.splice(randomIndex, 1);
return item[0];
}
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