Q933 How can I set the value of a form field when a check box is selected?

<script language="JavaScript"><!--
function setField(what) {
    if (what.myTick.checked)
        what.myText.value = 'checked';
    else
        what.myText.value = '';
}
//--></script>

<form>
<input type="checkbox" name="myTick" onClick="setField(this.form)">
<input type="text" name="myText">
</form>