How to evaluate a string on a regular expression rule in JavaScript

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JavaScript has a built in regular expression function for testing if a string arguments is matching the given regular expression rule;

Syntax of the regular expression tester is as follows;

/regex/.test(string)

Take for instance you want to test if a string contains only alphanumeric upper and lower case characters, space and numbers;

const str = "Eat code sleep"

/[A-Z,a-z,0-9, ]*/.test(str)
// returns boolean 'true'

Or in another example;

const str = "Eat, Code, Sleep"

/[A-Z,a-z,0-9, ]*/.test(str)
// returns boolean 'false'

Because commas are not included in the regular expression match rules.

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