How to replace multiple strings with other multiple strings at a time in javascript? [duplicate]

Answer 1

I'd prefer to store replacements as key-value pairs in an object or as an array of pairs. Regardless of the format, you can dynamically create a regex by joining the values you want to replace using | alternation. Then give replace a callback function and use its match parameter as a key to look up its corresponding pair in the swaps object.

const s = "I am Java";
const swaps = {am: "love", Java: "JS"};
const pattern = new RegExp(Object.keys(swaps).join("|"), "g");
console.log(s.replace(pattern, m => swaps[m]));

To handle case-insensitive replacements, ensure all keys in swaps are lowercase (either programmatically or manually, depending on usage) and lowercase the matches before keying in:

const s = "I am Java";
const swaps = {am: "love", java: "JS"};
const pattern = new RegExp(Object.keys(swaps).join("|"), "gi");
console.log(s.replace(pattern, m => swaps[m.toLowerCase()]));

Answer 2

This works.

String.prototype.replaceAll = function(str1, str2, ignore) {

  let flags = 'g';
  if (ignore) {
    flags += 'i';
  }

  if (Array.isArray(str1) && Array.isArray(str2)) {
    let newStr = this;

    str1.map((element, index) => {
      if (str2[index]) {
        newStr = newStr.replace(new RegExp(element, flags), str2[index]);
      }
      return newStr;
    });
    return newStr;
  }
  else {
    return this.replace(new RegExp(str1, flags), str2);
  }
}