need help to display letter pressed in a div with javascript

here's what i got so far, i get "undefined" in the div instead of the actual letter pressed.

<script language="JavaScript">
    document.onkeydown = checkKeycode;

    function checkKeycode(e) 
    {
        var keycode;
        if (window.event) 
        {
            keycode = window.event.keyCode;
        }
        else if (e) keycode = e.which;

        var character = String.fromCharCode(keycode);
        var letterDiv = document.getElementById("l开发者_JS百科etter1");
        letterDiv.innerHTML =character.innerHTML;
</script>

Here's JSFiddle Demo:

Set the letterDiv's innerHtml to that of var character not character.innerHTML. var character is a string not an Element.

document.onkeydown = checkKeycode;

    function checkKeycode(e) {
        var keycode;
        if (window.event) {
            keycode = window.event.keyCode;
        }
        else if (e) keycode = e.which;

        var character = String.fromCharCode(keycode);
        var letterDiv = document.getElementById("letter1");
        letterDiv.innerHTML = character;
    }

Remove innerHTML from character like so:

letterDiv.innerHTML = character;

Also, in your example, it appears that you are missing the end bracket } for your function. I suspect this problem does not exist in your actual project.