Capitalize first character of user input in real time with JQuery

Question

I am trying to auto-capitalize the first character of a textarea/input that the user inputs. The first attempt looked like this:

$(document).ready(function() {
 $('input').on('keydown', function() {
    if (this.value[0] != this.value[0].toUpperCase()) {
        // store current positions in variables
        var start = this.selectionStart;
        var end = this.selectionEnd; 
        this.value = this.value[0].toUpperCase() + this.value.substring(1);
        // restore from variables...
        this.setSelectionRange(start, end);
    }
 });
});

The problem with this is that it shows the lowercase character and then corrects it, which is ugly (http://jsfiddle.net/9zPTA/2/). I would like to run my javascript on keydown instead of keyup, and transform the event in flight (or intercept it, prevent default, and trigger a modified new event).

Here's what I have now, which doesn't work (http://jsfiddle.net/9zPTA/5/):

$(document).ready(function() {
  $('input').on('keydown', function(event) {
    if (this.selectionStart == 0 && event.keyCode >= 65 && event.keyCode <= 90 && !(event.shiftKey)) {
       event.preventDefault();
       var myEvent = jQuery.Event('keypress');
       myEvent.target = event.target;
       myEvent.shiftKey = true;
       myEvent.keyCode = event.keyCode;
       $(document).trigger(myEvent);
    }
  });
});

I'm not sure why this doesn't work - what am I missing here?

Answer 1

//First letter only(absolutely). eg. Tom tom, tom
//Note: "change paste" in this function ensures this will work even if the user pasted into the input or used the autocomplete.

$('#your-input').on('change paste keydown', function(e) {
    $th_inp = $(this).val();
    inp_val = $th_inp.charAt(0).toUpperCase()+$th_inp.slice(1);
    $(this).val(inp_val);
});

//First letter (including after punctuation). eg. Tom Tom, Tom

$('#your-input').on('change keydown paste', function(e) {
  if (this.value.length = 1) {}
    var $this_val = $(this).val();
    this_val = $this_val.toLowerCase().replace(/\b[a-z]/g, function(char) {
        return char.toUpperCase();
    });
    $(this).val(this_val);
});

Answer 2

Here is a fiddle I made that does what you want in Chrome. I'm not sure if it will work in other browsers.

Code:

$(document).ready(function() {
    $('input').on('keydown', function(event) {
        if (this.selectionStart == 0 && event.keyCode >= 65 && event.keyCode <= 90 && !(event.shiftKey) && !(event.ctrlKey) && !(event.metaKey) && !(event.altKey)) {
           var $t = $(this);
           event.preventDefault();
           var char = String.fromCharCode(event.keyCode);
           $t.val(char + $t.val().slice(this.selectionEnd));
           this.setSelectionRange(1,1);
        }
    });
});