Better way to sum a property value in an array

Question

I have something like this:

$scope.traveler = [
            {  description: \'Senior\', Amount: 50},
            {  description: \'Senior\', Amount: 50},
             


        

Answer 1

Here's a solution I find more flexible:

function sumOfArrayWithParameter (array, parameter) {
  let sum = null;
  if (array && array.length > 0 && typeof parameter === 'string') {
    sum = 0;
    for (let e of array) if (e && e.hasOwnProperty(parameter)) sum += e[parameter];
  }
  return sum;
}

To get the sum, simply use it like that:

let sum = sumOfArrayWithParameter(someArray, 'someProperty');