Simple type conversion in arrays using map

Type conversion is a big deal, but not anymore? Just use maps against a given array and them conversion shortcuts to simplify type conversion in Javascript.

Consider the below array -

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const nums = [1, 3, 5, 7, 9];

We can convert the type to string using a map.

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const nums = [1, 3, 5, 7, 9];
const numsStr = nums.map(val => String(val));
console.log("numsStr: ", numsStr);
// [ '1', '3', '5', '7', '9' ]

Since String by itself is a function, we can simplify the code further.

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const nums = [1, 3, 5, 7, 9];
const numsStr = nums.map(String);

console.log(numsStr);
// [ '1', '3', '5', '7', '9' ]

Similarly, we can convert an array of strings to array of numbers.

Using concepts demonstrated earlier, we could have done -

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const numsStr = ["1", "3", "5", "7", "9"];

const nums = numsStr.map(Number);

console.log(nums);
// [ 1, 3, 5, 7, 9 ]

.. and for Boolean type -

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const numsStr = ["1", "3", "5", "7", "9"];

const numsBool = numsStr.map(Boolean);

console.log(numsBool);
// [ true, true, true, true, true ]

Also see

Shortcuts for type conversion

Simple type conversion in arrays using map

Also see

See Also