Sum up "field num" in Types

[Yi]

In my project, the Type "Activities" has a field, which is "num". How to sum up these numbers of all items ? 
Is there a way to fetch the items in Type one by one in the cloud code?

For example, how to sum up the numbers from 41 to 37 in the attached?

[Anton Dobrev]

Hi Yi,

Thank you for your question.

We have prepared two examples:

•   the first returns the sum of all the items in the content type
•   the second returns the sum of all items for the current response

Both approaches are using a helper function that iterates over the items and returns the sum of the fields. It looks like this:

function sumArray(arr){
  var len = arr.length;
  var i;
  var sum = 0;
  var radix = 10;
  for(i = 0; i < len; i++){
    sum += parseInt(arr[i].Num, radix);
  }

  return sum;
}

1. If you want to explicitly sum all the items in the content type and return their sum, please add the following code in the appropriate event in the cloud code:

var data = Everlive.Sdk.$.data('Activities');
    data.get().
    then(function (data) {
          response.additionalData.TotalCount = sumArray(data.result);
            done();
        },
        function (err) {
            done();
 });

2. The next example sums up only the items returned for the current response(for example you can have a filter applied before retrieving the items, or retrieving all items).

Everlive.Events.afterRead(function(request, response, context, done) {
  var responseResult = response.result;
  if(responseResult){
    if(!Array.isArray(responseResult)){
      responseResult = [responseResult];
    }
    response.additionalData.TotalSum = sumArray(responseResult);
  }
    done();
});

Please, let us know if these examples are helpful for you. If you need more details or an implementation of a more specific scenario, do not hesitate to contact us.

Regards,
Anton Dobrev
Telerik