← Back to1 LOC

Check if a string is upper case

Written byPhuoc Nguyen
Created
19 Apr, 2020
Last updated
13 Oct, 2021
Category
Validator
JavaScript version
isUpperCase.js
const isUpperCase = (str) => str === str.toUpperCase();
TypeScript version
isUpperCase.ts
const isUpperCase = (str: string): boolean => str === str.toUpperCase();

Questions? 🙋

Do you have any questions? Not just about this specific post, but about any topic in front-end development that you'd like to learn more about? If so, feel free to send me a message on Twitter or send me an email. You can find them at the bottom of this page.
I have a long list of upcoming posts, but your questions or ideas for the next one will be my top priority. Let's learn together! Sharing knowledge is the best way to grow 🥷.

Recent posts ⚡

Create your own custom cursor in a text area
soon
Highlight the current line in a text area
soon
Display a menu at the cursor position in a text area
soon
Mirror a text area for improving user experience
26 Sep, 2023
Calculate the coordinates of the current cursor in a text area
26 Sep, 2023
Jump to the beginning or end of the current line in a text area
25 Sep, 2023
Display the line numbers in a text area
24 Sep, 2023
Select a given line in a text area
24 Sep, 2023
Count how many lines a given string takes up in a text area
24 Sep, 2023
Highlight keywords in a text area
23 Sep, 2023
Calculate the reading time of a webpage
23 Sep, 2023
createDocumentFragment vs createElement
22 Sep, 2023
Enter full-screen mode
22 Sep, 2023
Make an element take up the entire page
22 Sep, 2023
Dynamically update CSS root variables
21 Sep, 2023
See more→

Newsletter 🔔

If you're into front-end technologies and you want to see more of the content I'm creating, then you might want to consider subscribing to my newsletter.
By subscribing, you'll be the first to know about new articles, products, and exclusive promotions.
Don't worry, I won't spam you. And if you ever change your mind, you can unsubscribe at any time.