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Check if a string contains only letters and numbers

Written byPhuoc Nguyen
08 Jun, 2020
Last updated
13 Oct, 2021
JavaScript version
const isAlphanumeric = (str) => /^[0-9A-Z]+$/i.test(str);
TypeScript version
const isAlphanumeric = (str: string): boolean => /^[0-9A-Z]+$/i.test(str);
isAlphanumeric('helloworld'); // true
isAlphanumeric('HelloWorld'); // true
isAlphanumeric('hello world'); // false
isAlphanumeric('hello123'); // true
isAlphanumeric('hello 123'); // false

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