How to Convert a String to an Integer in JavaScript
By FoxLearn 9/6/2024 1:50:03 AM 133
How do I convert a string to an integer in JavaScript?
1. Using parseInt()
to convert string to int
The parseInt()
function parses a string and returns an integer.
For example:
let str = "1234"; let num = parseInt(str, 10); // 10 is the radix for decimal numbers console.log(num); // 1234
It also allows you to specify the radix (base) of the number system.
2. Using the Unary Plus Operator (+
) to convert string to int
If your string is already in the form of an integer, you can use unary plus operator to convert to integer.
For example:
let str = "1234"; let num = +str; console.log(num); // 1234
The unary plus operator is a quick and concise way to convert a string to a number.
3. Using the Number()
Function to convert string to int
The Number()
function converts a value to a number.
For example:
let str = "1234"; let num = Number(str); console.log(num); // 1234
4. Using Math.floor()
, Math.ceil()
, or Math.round()
to convert string to int
If you need to ensure that the result is an integer, you can use the functions below.
For example:
let str = "1234.43"; let num = Math.floor(Number(str)); // Converts to 1234 console.log(num); num = Math.ceil(Number(str)); // Converts to 1235 console.log(num); num = Math.round(Number(str)); // Converts to 1234 console.log(num);
If the string cannot be converted to an integer (e.g., "abcd"), parseInt()
will return NaN
(Not-a-Number). Similarly, Number()
will also return NaN
for non-numeric strings.
The unary plus operator and Number()
function handle floating-point numbers as well. If you specifically need an integer, you might need to use additional methods like Math.floor()
, Math.ceil()
, or Math.round()
.
- How to Handle Button Clicks Using jQuery
- How to convert string into number in Javascript
- How to get datatype in JavaScript
- How to convert string to boolean in Javascript
- How to fix 'Fetch request to https:www.google.com fails with CORS'
- How to Check Internet Connection Status in Javascript
- How to download file using JavaScript
- How to get selected option in JQuery