js parse text string first letter capital and make others letter lowercase code example

Example 1: javascript first letter uppercase

const upperCase = function(names){
    const toLower = names.toLowerCase().split(' ');
    const namesUpper = [];
    for(const wordName of toLower){
        namesUpper.push(wordName[0].toUpperCase() + wordName.slice(1));
    }
    return namesUpper.join(' ');
}

Example 2: js capitalize word

const capitalizeFirstLetter(string) => 
	string.charAt(0).toUpperCase() + string.slice(1).toLowerCase()