JavaScript: Extend String Object: Attach toUpperCase() Method to String.prototype

Using a String.prototype Method to Check for All UpperCase Letters

Captured from Node.js REPL

Lengths for Comparison

match() along with a regex pattern parameter, followed by length(), were used to count the uppercase letters (including spaces) below. Total length of the entire string were also returned:

> s = 'CAPITALIZED CHARACTERS'
'CAPITALIZED CHARACTERS'
> s.match(/[A-Z\s]/g).length
22
> s.length
22
>

Regex Pattern

The regex pattern /[A-Z\s]/g has three basic aspects:

• [A-Z] matches uppercase letters
• \s matches spaces between words
• g indicates every matching character

> s = 'CAPITALIZED'
'CAPITALIZED'
> s.match(/[A-Z\s]/g)
[ 'C', 'A', 'P', 'I', 'T', 'A', 'L', 'I', 'Z', 'E', 'D' ]
>