Fange klik på knap med dynamisk navngivet ID

<button onclick="foo(this.id)" id="unixtime1234567890">Knap</button>

function clickEventDelegate( e ) {
    var elmTarget = e ? e.target : event.srcElement;
    if (elmTarget.id.indexOf("TimerButton_") == 0) {
        TimerButtonClicked(elmTarget)
    }
    else ShowMessage( "Clicked: " + elmTarget.nodeName + " " + elmTarget.id );
}

function TimerButtonClicked( btn ) {
    var timeFromId = btn.id.split("_")[1];
    ShowMessage("Time Clicked: " + timeFromId) ;
}

function ShowMessage( txt ) {
    document.getElementById("Message").firstChild.nodeValue = txt;
}

window.onload = function () {
    document.body.onclick = clickEventDelegate;
}