Insert special characters in textbox

Question

So I have a textbox and I want to add some text( without deleting the one I already have) by clicking a button.. is that possible?

The text I'll be adding will be some html special characters code like é to show a "é"...

or maybe do the reverse, like I write a "é" and then when I submit it changes to é this way it will be easier to the user

Thanks in advance

Answer 1

<input type="text" id="txt" />
<input type="button" value="Addtext" onclick="addText()" />
<script>
    function addText() {
        document.getElementById('txt').value += "sometextàéèìòù";
    }
</script>