I tried to get the sum of this JSON array values. But I don't know the right way to to do this.
var taxes = [ {"1": 11}, {"2": 33} ];
result = 44;
3 Answers
You can use .reduce() to calculate sum like this:
let taxes = [{"1":11}, {"2":33}];
let result = taxes.reduce((a, c) => a + c[Object.keys(c)], 0);
console.log(result);In case your objects are having consecutive numbers as properties you can use a simpler approach like:
let taxes = [{"1":11}, {"2":33}];
let result = taxes.reduce((a, c, i) => a + c[i + 1], 0);
console.log(result);7 Comments
Barmar
You're assuming that the property name in each object will always be sequential integers. I'm not sure I would extrapolate that from an example of just two elements.
Mohammad Usman
@Barmar Yes, you are right. But may be objects are having consecutive numbers as properties. OP should clarify this.
Barmar
I generally ask for such clarification in a comment before posting an answer, or I make the assumption clear in my answer.
Mohammad Usman
@Barmar I've tried to add an alternate approach which is not dependent on any condition and hopefully will work in any similar case.
Barmar
Can you explain how
c[[Object.keys(c)]] works in that example? Why double brackets? |
If each object in the array only has 1 key/value pair, this will work regardless if the keys are sequential:
const result = taxes.reduce((a, b) => a += Object.values(b)[0], 0);
Comments
You can try with Array.prototype.map() and Array.prototype.reduce()
var taxes = [{"1":11},{"2":33}];
const result = taxes.map(a=>Object.values(a)).reduce((a,b)=>parseInt(a)+parseInt(b))
console.log("result = "+result);
answered Apr 25, 2018 at 17:24
A l w a y s S u n n y
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reduceand then provide what you've tried and what doesn't work. developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…