Count empty strings in an array [duplicate]

Question

Having this input:

const myArray = ["", "", "test"];

I want to count the number of empty strings, for the above example it is 2. A complicated method would be

myArray.map(a => a.length === 0) which returns a new array of true and false and after that to count them.

Is there a shorter method to do this?

Does this answer your question? Count instances of string in an array — Tushar Shahi
– Tushar Shahi, Commented Jul 7, 2021 at 8:46
If you can count true and false, why can't you count the emptystring ""? — derpirscher
– derpirscher, Commented Jul 7, 2021 at 8:46

Baboo · Accepted Answer · 2021-07-07 08:47:14Z

2

You can filter the undesired values and then check the length of the resulting array:

const emptyCount = myArray.filter(a => a.length === 0).length;

answered Jul 7, 2021 at 8:47

Baboo

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Comments

Giovanni Esposito · Accepted Answer · 2021-07-07 08:46:58Z

2

You could use filter and use length in this way:

const myArray = ["", "", "test"];

let count = myArray.filter(x => x.length === 0).length;

console.log(count);

answered Jul 7, 2021 at 8:46

Giovanni Esposito

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ikhvjs · Accepted Answer · 2021-07-07 08:47:44Z

1

You can use filter() to get a filtered array with only empty string item. Then you can get the number of item in the array with length.

const myArray = ["", "", "test"];

const output = myArray.filter(el => el === "").length;

console.log(output);

answered Jul 7, 2021 at 8:47

ikhvjs

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