function doClick(e, buttonid){
    var evt = e ? e : window.event;
    var bt = document.getElementById(buttonid);
    if (bt){
        if (evt.keyCode == 13){
            bt.click();
            return false;
        }
    }
}


function addEvent(obj, evType, fn) {
    if (obj.addEventListener) {
        obj.addEventListener(evType, fn, false);
        return true;
    } else if (obj.attachEvent) {
        var r = obj.attachEvent("on" + evType, fn);
        return r;
    } else {
        return false;
    }
}
function removeEvent(obj, evType, fn, useCapture) {
    if (obj.removeEventListener) {
        obj.removeEventListener(evType, fn, useCapture);
        return true;
    } else if (obj.detachEvent) {
        var r = obj.detachEvent("on" + evType, fn);
        return r;
    } else {
        alert("Handler could not be removed");
    }
}

/**
* Code below taken from - http://www.evolt.org/article/document_body_doctype_switching_and_more/17/30655/
*
* Modified 4/22/04 to work with Opera/Moz (by webmaster at subimage dot com)
*
* Gets the full width/height because it's different for most browsers.
*/
function getViewportHeight() {
    if (window.innerHeight != window.undefined) return window.innerHeight;
    if (document.compatMode == 'CSS1Compat') return document.documentElement.clientHeight;
    if (document.body) return document.body.clientHeight;

    return window.undefined;
}
function getViewportWidth() {
    var offset = 17;
    var width = null;
    if (window.innerWidth != window.undefined) return window.innerWidth;
    if (document.compatMode == 'CSS1Compat') return document.documentElement.clientWidth;
    if (document.body) return document.body.clientWidth;
}

/**
* Gets the real scroll top
*/
function getScrollTop() {
    if (self.pageYOffset) // all except Explorer
    {
        return self.pageYOffset;
    }
    else if (document.documentElement && document.documentElement.scrollTop)
    // Explorer 6 Strict
    {
        return document.documentElement.scrollTop;
    }
    else if (document.body) // all other Explorers
    {
        return document.body.scrollTop;
    }
}
function getScrollLeft() {
    if (self.pageXOffset) // all except Explorer
    {
        return self.pageXOffset;
    }
    else if (document.documentElement && document.documentElement.scrollLeft)
    // Explorer 6 Strict
    {
        return document.documentElement.scrollLeft;
    }
    else if (document.body) // all other Explorers
    {
        return document.body.scrollLeft;
    }
}

function changeClass(element, toClass) {
    if (document.getElementById(element) != null) {
        document.getElementById(element).className = toClass;
    }
}