javascript - Convert first letter to uppercase on input box

Question

JS Bin demo

This regex transform each lower case word to upper case. I have a full name input field. I do want the user to see that each word's first letter he/she pressed is converted to uppercase in the input field.

I have no idea how to properly replace the selected characters in the current input field.

$('input').on('keypress', function(event) {
  var $this = $(this),
      val = $this.val(),
      regex = /[a-z]/g;

  val = val.toLowerCase().replace(regex, function(letter) {
    return letter.toUpperCase();
  });

  // I want this value to be in the input field.
  console.log(val);
});

Answer 1

Given i.e: const str = "hello world" to become Hello world

const firstUpper = str.substr(0, 1).toUpperCase() + str.substr(1);

or:

const firstUpper = str.charAt(0).toUpperCase() + str.substr(1);

or:

const firstUpper = str[0] + str.substr(1);