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javascriptobjectcamelcasing

How to find and remove all underscores, and make the next letter after the underscore uppercase

i have object with underscores keys

const obj = { api_key: 1, is_auth: false }

i want to get camelCase keys

const obj = { apiKey: 1, isAuth: false }

Solution

  • You can map the keys using a regular expression to replace the underscores and following character with an uppercased character. Something like:

    const obj = {
  api_key: 1,
  is_true: false,
  all___under_scores: true,
  _test: "Tested",
  test_: "TestedToo (nothing to replace)",
};
const keys2CamelCase = obj => Object.fromEntries(
  Object.entries(obj)
  .map(([key, value]) => 
    [key.replace(/_{1,}([a-z])/g, (a, b) => b.toUpperCase()), value])
);

console.log(keys2CamelCase(obj));

    If you also want to remove trailing underscores use

    key.replace(/_{1,}([a-z])|_$/g, (a, b) => b && b.toUpperCase() || ``)