JavaScript: Convert a string to snake case

JavaScript fundamental (ES6 Syntax): Exercise-120 with Solution

Write a JavaScript program to convert a string to snake case.

Note: Break the string into words and combine them adding _ as a separator, using a regexp.

• Use String.prototype.match() to break the string into words using an appropriate regexp.
• Use Array.prototype.map(), Array.prototype.slice(), Array.prototype.join() and String.prototype.toLowerCase() to combine them, adding _ as a separator.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
const toSnakeCase = str =>
  str &&
  str
    .match(/[A-Z]{2,}(?=[A-Z][a-z]+[0-9]*|\b)|[A-Z]?[a-z]+[0-9]*|[A-Z]|[0-9]+/g)
    .map(x => x.toLowerCase())
    .join('_');

console.log(toSnakeCase('camelCase'));
console.log(toSnakeCase('some text'));
console.log(toSnakeCase('some-mixed_string With spaces_underscores-and-hyphens'));
console.log(toSnakeCase('AllThe-small Things'));
console.log(toSnakeCase('IAmListeningToFMWhileLoadingDifferentURLOnMyBrowserAndAlsoEditingSomeXMLAndHTML'));

Sample Output:

camel_case
some_text
some_mixed_string_with_spaces_underscores_and_hyphens
all_the_small_things
i_am_listening_to_fm_while_loading_different_url_on_my_browser_and_also_editing_some_xml_and_html

Pictorial Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-120-1 by w3resource (@w3resource) on CodePen.

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