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Eduardo Diaz
Eduardo Diaz
Courses Plus Student 6,048 Points

Checking if an object has multiple keys ?

I have an array of object:

const arr =  [
 {a:1, b:1, c:1},
 {a:2, b:2, c:3}

I want to check that each element on the list contains the keys a, b, c

arr.every(item => item.hasOwnProperty('a','b','c'));

However hasOwnProperty only checks for the first property and not all of them.

I could

arr.every(item => item.hasOwnProperty('a','1')

But then I'll get a true value.

1 Answer

Steven Parker
Steven Parker
215,372 Points

You were close the 2nd time, you just need to check each property separately:

arr.every(item => item.hasOwnProperty("a")
               && item.hasOwnProperty("b")
               && item.hasOwnProperty("c") );