js regex matching specific chars code example

Example 1: regex for strings with specific letters javascript

let re = /ab+c/;

Example 2: javascript regex match character from a set of characters

// Regex - Any character from a set of characters
console.log(/[0123456789]/.test("in 1992")); // true
console.log(/[0-9]/.test("in 1992")); // true
console.log(/[abc]/.test("def")); // false
console.log(/[abc]/.test("cdef")); // true