Convert a string array to a number array in JavaScript

This post will discuss how to convert a string array to a number array in JavaScript.

There are several ways to convert a string array to a number array in JavaScript. Here are some of the most common functions:

1. Using `Array.map()` function

The Array.map() function creates a new array by applying a function to each element of the original array. We can use it with the Number() function, which is the standard function to convert a string to a number. The map() function applies the Number() function to each element of the string array and returns a new array of numbers with the results. Here’s an example:

let stringArray = ["1", "2", "3", "4", "5"];

let intArray = stringArray.map(Number);

console.log(intArray); // [1, 2, 3, 4, 5]

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Another option is to use the parseInt() function with the map() function. The parseInt() function parses a string and returns an integer. The map() function applies the parseInt() function to each element of the string array and returns a new array of integers. The parseInt() function takes a second argument that specifies the radix (base) of the input string. Here’s an example:

let stringArray = ["1", "2", "3", "4", "5"];

let intArray = stringArray.map(function(str) {

return parseInt(str, 10);

});

console.log(intArray); // [1, 2, 3, 4, 5]

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We can also use this function to create a new array with the results of applying the unary plus operator (+) to every element in the original array. The unary plus operator converts a string to a number. Here’s an example:

let stringArray = ["1", "2", "3", "4", "5"];

let intArray = stringArray.map(str => +str);

console.log(intArray); // [1, 2, 3, 4, 5]

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Note if the string is not a valid number, all the above mapping functions returns NaN (Not a Number). For example, a string array like ["1", "two", "3"] will result in the array [1, NaN, 3].

2. Using `push()` function

The push() function adds one or more elements to the end of an array. We can use a for loop or a for…of loop to iterate over the string array and convert each element to a number using the appropriate mapping functions. Then we can use the push() function to add the converted element to a new array. Here’s an example using the Number() function:

let stringArray = ["1", "2", "3", "4", "5"];

let intArray = [];

for (let str of stringArray) {

intArray.push(Number(str));

}

console.log(intArray); // [1, 2, 3, 4, 5]

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We can also use forEach() function to iterate over the original array and push the parsed integer values to a new array. Here’s an example using the parseInt() function:

let stringArray = ["1", "2", "3", "4", "5"];

let intArray = [];

stringArray.forEach(x => intArray.push(parseInt(x, 10)));

console.log(intArray); // [1, 2, 3, 4, 5]

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That’s all about converting a string array to a number array in JavaScript.

Convert a string array to a number array in JavaScript

1. Using Array.map() function

2. Using push() function

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1. Using `Array.map()` function

2. Using `push()` function