JavaScript: Capitalize the first letter of a string

JavaScript fundamental (ES6 Syntax): Exercise-263 with Solution

Write a JavaScript program to capitalize the first letter of a string.

• Use array destructuring and String.prototype.toUpperCase() to capitalize the first letter of the string.
• Use Array.prototype.join('') to combine the capitalized first with the ...rest of the characters.
• Omit the lowerRest argument to keep the rest of the string intact, or set it to true to convert to lowercase.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const capitalize = ([first, ...rest], lowerRest = false) =>
  first.toUpperCase() + (lowerRest ? rest.join('').toLowerCase() : rest.join(''));

console.log(capitalize('fooBar')); 
console.log(capitalize('fooBar', true));

Sample Output:

FooBar
Foobar

Pictorial Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-263-1 by w3resource (@w3resource) on CodePen.

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