Friends, We are having an array categories of scope variable. Need to get count of checked(checked: true) categories without using for loop. Is there any way? Please suggest. Thanx.
$scope.categories = [
{categoryId : '1', checked: true},
{categoryId : '2', checked: true},
{categoryId : '3', checked: false},
{categoryId : '4', checked: false}
];
You say you don't want to loop, however don't explain why? I don't think you can avoid a loop if you have an unknown length of array. In your case, a filter may do the trick.
Update for clarity
This will use a loop in the background.
var count = $scope.categories.filter(function(cat) {
return cat.checked === true
}).length;
=== true part only serves to ensure the checked property is true and not some other truthy value.
for loop for some reason. Even though filter may in the background.Assuming your data is:
$scope.categories = [
{categoryId : '1', checked: true},
{categoryId : '2', checked: true},
{categoryId : '3', checked: false},
{categoryId : '4', checked: false}
];
var total = $scope.categories.reduce(function(t,item){
return t + +item.checked;
},0)
If you really want to avoid using any kind of loop you have to know the amount of items in your array in advance.
Assuming your example is fixed data, then you can simply use this
var count = $scope.categories[0].checked + $scope.categories[1].checked + $scope.categories[2].checked + $scope.categories[3].checked
to get the count. Any other solution will use a loop of some sort.
In computer programming, a loop is a sequence of instruction s that is continually repeated until a certain condition is reached.
Using underscore/lodash:
var count = _.filter($scope.categories, {checked: true}).length;
