capitalize first letter in each word javascript

function titleCase(str) {
   var splitStr = str.toLowerCase().split(' ');
   for (var i = 0; i < splitStr.length; i++) {
       // You do not need to check if i is larger than splitStr length, as your for does that for you
       // Assign it back to the array
       splitStr[i] = splitStr[i].charAt(0).toUpperCase() + splitStr[i].substring(1);     
   }
   // Directly return the joined string
   return splitStr.join(' '); 
}

document.write(titleCase("I'm a little tea pot"));const str = 'captain picard';

function capitalize(str) {
  return str.charAt(0).toUpperCase() + str.slice(1);
}

const caps = str.split(' ').map(capitalize).join(' ');
caps; // 'Captain Picard'search function

<ion-input [(ngModel)]="keyword" (ngModelChange)="toTitleCase($event)"  class="input-container" placeholder="Enter Input"></ion-input>


function capital_letter(str) 
{
    str = str.split(" ");

    for (var i = 0, x = str.length; i < x; i++) {
        str[i] = str[i][0].toUpperCase() + str[i].substr(1);
    }

    return str.join(" ");
}

console.log(capital_letter("Write a JavaScript program to capitalize the first letter of each word of a given string."));

const titleCase = function(text) {
  let newText = '';
  text = text.toLowerCase();
  text = text.charAt(0).toUpperCase() + text.slice(1);
  for (let i = 0; i < text.length; i++) {
    if (text[i] === ' ') {
      newText += ' ' + text[i+1].toUpperCase();
      i++;
    } else {
      newText += text[i];
    }
  }
  return newText;
}