JavaScript: Create a new string with the results of calling a provided function on every character in the calling string

JavaScript fundamental (ES6 Syntax): Exercise-83 with Solution

Write a JavaScript program to create an updated string with the results of calling a provided function on every character in the called string.

• Use String.prototype.split('') and Array.prototype.map() to call the provided function, fn, for each character in str.
• Use Array.prototype.join('') to recombine the array of characters into a string.
• The callback function, fn, takes three arguments (the current character, the index of the current character and the string mapString was called upon).

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const mapString = (str, fn) =>
  str
    .split('')
    .map((c, i) => fn(c, i, str))
    .join('');

console.log(mapString('Javascript exercises', c => c.toUpperCase()));

Sample Output:

JAVASCRIPT EXERCISES

Pictorial Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-83-1 by w3resource (@w3resource) on CodePen.

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