test regex o nstring code example

Example 1: javascript regex .test

const str = 'hello world!';
const result = /^hello/.test(str);

console.log(result); // true

/**
The test() method executes a search for a match between 
a regular expression and a specified string
*/

Example 2: regex /

// replaces all / in a String with _
str = str.replace(/\//g,'_');