proper case in javascript code example

Example 1: string to title case javascript

function titleCase(sentence) {
  let sentence = string.toLowerCase().split(" ");
  for (let i = 0; i < sentence.length; i++) {
    sentence[i] = sentence[i][0].toUpperCase() + sentence[i].slice(1);
  }
  
  return sentence.join(" ");
}

Example 2: snentence case capitalisation js

const string = "tHIS STRING'S CAPITALISATION WILL BE FIXED."
const string = string.charAt(0).toUpperCase() + string.slice(1)

Example 3: javascript string proper case

function toTitleCase(str) {
  return str.replace(
    /\w\S*/g,
    function(txt) {
      return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
    }
  );
}
// example
toTitleCase("the pains and gains of self study");
// "The Pains And Gains Of Self Study"