Clash Royale CLAN TAG#URR8PPP

Returning a single value from a filter

I am trying to return a single value from a filter that returns a large object.

return data.filter(subject => subject.id === 1)
.map((subject) =>
return subject.total.toString();
);


I have tried, toString, JSON.parse and a few more but always get it either as a single array value.

[112]

or a string inside the array

["112"]

but not a single returned value

112

Is map the wrong method? How do I return a pure integer or string would do?

filter

array

4 Answers
4

You just need to pick the first element. This should suffice..

return data.filter(subject => subject.id === 1)[0].total+""


find

Instead of filter which returns an array with filtered values, use find:

filter

find

const subject = data.find(subject => subject.id === 1);
return subject.total.toString();


or shorter:

return data.find(subject => subject.id === 1).total.toString();


What about

return data
.filter(subject => subject.id === 1)
.map(subject => subject.total.toString())[0] // Take the first element of the array :)


Array.map returns an array. If your initial array contains one element, the output array will also contain one element. Just extract it with [0].

Array.map

[0]

Alternatively. find() returns one object :

find()

return data.find(subject => subject.id === 1).total.toString()


Filter will always return a array to get the first element use pop

pop

return data.filter(subject => subject.id === 1)
.map((subject) =>
return subject.total;
).pop();


By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.