Javascript - Replace all commas in a string

Unleash the power of replaceAll

Rise, modern JavaScript! Conjure String.prototype.replaceAll(), which does exactly what it promises: it vanquishes all occurrences without the need for a cryptic regex.

let str = "apple, banana, cherry";
str = str.replaceAll(",", "");
// Through the power of replaceAll: "apple banana cherry"
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Negotiate special regex characters

Special characters, those regex prima donnas like ., *, or +, can throw a diva fit when replaced improperly. Call upon an escape function to manage their diva effects:

function escapeRegex(string) {
  return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}
let str = "apple, banana, cherry, more.";
str = str.replace(new RegExp(escapeRegex(","), 'g'), "");
// Escape artist foiled, we're left with: "apple banana cherry more."
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The split and join relay race

When replace or replaceAll fail to meet our browser compatibility expectations, we can summon the dynamic duo of split() and join() for a reliable alternative:

let str = "apple, banana, cherry";
str = str.split(",").join("");
// Split-and-Join tactic delivers: "apple banana cherry"
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Split makes us a nice array of substrings, and join assembles them back into a single string like a well-versed master of jigsaw puzzles — with an optional new separator.

The versatility of RegExp constructor

For reusable and organized code, let's put our regex into an object, ala RegExp. Have your regex handy, ready for action:

const commaRegex = new RegExp(",", "g");
let str = "apple, banana, cherry";
str = str.replace(commaRegex, "");
// Empowered by RegExp constructor: "apple banana cherry"
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No browser left behind

Newer methods like replaceAll() are hip, but they may not vibe with older browsers. Use polyfills to give these old souls a helping hand:

if (!String.prototype.replaceAll) {
  String.prototype.replaceAll = function(str, newStr) {
    // If `str` is a string, employ the traditional replace
    if (typeof str === 'string') {
      while(this.indexOf(str) !== -1) {
        this.replace(str, newStr);
      }
      return this;
    }
    // If `str` is a regex, summon `replace()` with the 'g' lobal charm
    return this.replace(new RegExp(str, 'g'), newStr);
  };
}
// Ensuring every browser gets to join the party, gracefully.
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