Get first letter of each Word in a String in JavaScript

Get first letter of each Word in a String in JavaScript #

To get the first letter of each word in a string:

1. Use the String.split() method to split the string into an array of words.
2. Use the map() method to iterate over the array and get each first letter.
3. Use the Array.join() method to join the array into a string.

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function getFirstLetters(str) {
  const firstLetters = str
    .split(' ')
    .map(word => word.charAt(0))
    .join('');

  return firstLetters;
}

// 👇️ ABC
console.log(getFirstLetters('Alice, Bob, Charlie'));

// 👇️ BHC
console.log(getFirstLetters('Bobby   Hadz   Com.'));

We used the String.split() to split the string into an array of words.

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// 👇️ ['Hello', 'world']
console.log('Hello world'.split(' '));

The function we passed to the Array.map method gets called with each element in the array.

The map() method returns a new array containing the values returned from the callback function.

In this case, an array containing the first letter of each word.

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// 👇️ ['H', 'w']
console.log('Hello world'.split(' ').map(word => word.charAt(0)));

The last step is to use the Array.join() method to join the array into a string.

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console.log(
  'Hello world'
    .split(' ')
    .map(word => word.charAt(0))
    .join(''),
); // 👉️ "Hw"

console.log(
  'Hello world'
    .split(' ')
    .map(word => word.charAt(0))
    .join(' '),
); // 👉️ "H w"

The Array.join() method concatenates all of the elements in an array using a separator.

The only argument the Array.join() method takes is a separator - the string used to separate the elements of the array.

If the separator argument is set to an empty string, the array elements are joined without any characters in between them.

Alternatively, you can use the String.match() method.

Get first letter of each Word in a String using String.match #

To get the first letter of each word in a string:

1. Use the String.match() method to get an array of the first letters in the string.
2. Use the Array.join() method to join the array into a string.

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function getFirstLetters(str) {
  const firstLetters = str.match(/\b\w/g).join('');

  return firstLetters;
}

// 👇️ ABC
console.log(getFirstLetters('Alice, Bob, Charlie'));

// 👇️ BHC
console.log(getFirstLetters('Bobby   Hadz   Com.'));

The String.match method matches a string against a regular expression.

The method returns an array containing the matches (if any) or null if no matches are found.

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// 👇️ [ 'A', 'B', 'C' ]
console.log('Alice, Bob, Charlie'.match(/\b\w/g));

// 👇️ [ 'B', 'h', 'c' ]
console.log('Bobby hadz com'.match(/\b\w/g));

We passed a regular expression to the String.match method.

The forward slashes / / mark the beginning and end of the regular expression.

The \b character matches a word boundary - the position where a word character is not followed by or preceded by another word character.

We used the \b character to match characters at the beginning of the string (not preceded by anything) or characters preceded by spaces.

The \w special character matches Latin characters [a-zA-Z], numbers [0-9] and underscore _.

We used the g flag because we want to match all occurrences of first characters and not just the first occurrence.

The last step is to use the Array.join() method to join the array into a string.

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// 👇️ ABC
console.log('Alice, Bob, Charlie'.match(/\b\w/g).join(''));

// 👇️ Bhc
console.log('Bobby hadz com'.match(/\b\w/g).join(''));

Which approach you pick is a matter of personal preference. I'd use the split() and map() approach as I find it more readable.