键盘事件Ctrl+Enter

<textarea id="txt1" rows="10" cols="40"></textarea><br />
<input id="txt2" type="text" />
<input id="btn1" type="button" value="留言"/> 


<script>
window.onload = function() {
    var oBtn = document.getElementById('btn1');
    var oTxt1 = document.getElementById('txt1');
    var oTxt2 = document.getElementById('txt2');
    oBtn.onclick = function() {
        oTxt1.value += oTxt2.value + '\n';
        oTxt2.value = '';
    };
    oTxt2.onkeydown = function(ev) {
        var oEvent = ev || event;
        if (oEvent.ctrlKey && oEvent.keyCode == 13) {
            oTxt1.value += oTxt2.value + '\n';
            oTxt2.value = '';
        }
    }
}
</script>