Removing undefined values from Array

Question

In certain situations, it may happen that we have undefined or generally falsy values in Array structures. For instance when reading and filling data f

Answer 1

var data = Object.keys(data)

This will remove undefined values but array index will change

Answer 2

var arr1 = [NaN, 0, 15, false, -22, '',undefined, 47, null];

var array1 = arr1.filter(function(e){ return e;});

document.write(array1);

single lined answer

Answer 3

data.filter(Boolean)

Is the most short and readable way to do it.

Answer 4

As Diogo Capela said, but where 0 is not filtered out as well.

[].filter(item => item !== undefined && item !== null)

Answer 5

If you have an array of objects and want to remove all null and undefined items:

[].filter(item => !!item);

Answer 6

Inline using lambda

result.filter(item => item);