Fill text box through keyboard events javascript

Question

I neeed to fill in an input box using keyboard events 'keydown' 'keypress' and 'keyup' for running some test cases .I tried with following code

var fireKeyEvent = function(eventType,element,keyCode) {
    var keyboardEvent = jQuery.Event(eventType);
    keyboardEvent.which = keyCode;
    keyboardEvent.keyCode = keyCode;
    $(element).trigger(keyboardEvent);

}

i have the following html element

<input type='text' id='input'>

i tried firing following

fireKeyEvent('keydown',$('#input'),49);
fireKeyEvent('keypress',$('#input'),49);
fireKeyEvent('keyup',$('#input'),49);

where 49 is the ascii code of 1 so it should insert 1 into the text box. But it doesnt seem to insert anything into the text box.can someone help?