Angular - get data length without using ng-repeat

Question

I'm working with angular, and i need to be able to display an array length but without using ng-repeat .

here's the scenario:

I have default.json:

{
 { ...
   "data":
      [{
        "name":"Test",
        "errors":
          [
           {"id": 1,"level": 2,"details": {...}},
           {"id": 3,"level": 1},
           {"id": 5,"level": 1},
           {"id": 5,"level": 1},
           ....
          ],
        },
        {
         "name":"Test",
         "errors":
          [
           {"id": 1,"level": 2,"details": {...}},
           {"id": 5,"level": 1},
           ....
          ],
        }
      ],
    ....
  }
}

then I've created myData from the controller, so that I can do something like ng-repeat="data in myData" and i can use it properly.

Now, here's the question:

I Need to have a recap of all the errors, a sum of all the errors in the objects.

I tried to do something like this:

<span ng-repeat="data in myData">
<i ng-repeat="error in data.errors">{{error.length}}</i>
</span>

and nothing was printed. So I tried:

<span ng-repeat="data in myData">
<i>{{data.errors.length}}</i>
</span>

and the result was:

4 2 0 0 0 0 0

and it makes sense, because my first object as 4 errors, my second one 2 and so on...

But what I'd like to see is only: 6 , as there are 6 errors in total.

How can I get only one value that sums all the errors from all the objects I've got without having to use ng-repeat (I think I don't need it there)

Hope this question is clear enough, thanks for your help.

Answer 1

You should do in this way in your controller

 var sum=0;
 for(var i=0;i<$scope.MyData.length;i++)
 {
   var error=[];
   error=$scope.MyData[i].errors;
   sum=sum+error.length;

 }
 alert(sum+'');

Answer 2

use this code in the controller (updated for the promise)

function countErrors(myData) {
  $scope.totalErrors = myData
    .map(function(data) { 
      return data.errors.length; })
    .reduce(function(acc, errorsLenght){
      return acc += errorsLenght }, 0)
}
$scope.myData.$promise.then(countErrors)

Answer 3

A possible solution is to use reduce , so you can use the reduce like this

var result = array.reduce((prev, curr) => prev + curr);

if the array is [4,2,0] the result it will be 6

so a possible solution will be on the markup call a function in scope

{{arraySum(data.errors.length)}}

and the function will be

$scope.arraySum= function(array) {
    return array.reduce((prev, curr) => prev + curr);
}

EDIT for this edit we will use the function map

markup

{{totalErrors()}}

code

$scope.totalErrors = function(){
    if ($scope.myData)
        return $scope.myData.data.map(function(o){ return o.errors.length})
                                 .reduce((prev,curr) => {return prev + curr})
}

I have created a plunker from what i understand that is your data you can see it working here

Here is a plunker that simulates the delay of an ajax request using $timeout. It uses ng-cloak on markup to prevent displaying raw data.