how to change uppercase to lowercase with regex javascript

A solution without regex:

function isUpperCase(str) {
        return str === str.toUpperCase();
    }

var str = "It's around August AND THEN I get an email";
var matched = str.split(' ').map(function(val){
  if (isUpperCase(val) && val.length>1) {
    return val.toLowerCase();
    }
  return val;        
});

console.log(matched.join(' '));

Use /\b[A-Z]{2,}\b/g to match all-caps words and then .replace() with a callback that lowercases matches.

var string = "It's around August AND THEN I get an email",
  regex = /\b[A-Z]{2,}\b/g;

var modified = string.replace(regex, function(match) {
  return match.toLowerCase();
});

console.log(modified);
// It's around August and then I get an email

Also, feel free to use a more complicated expression. This one will look for capitalized words with 1+ length with "I" as the exception (I also made one that looked at the first word of a sentence different, but that was more complicated and requires updated logic in the callback function since you still want the first letter capitalized):

\b(?!I\b)[A-Z]+\b

Tags:

Javascript

Regex

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