var imgPrefix = 'vakantiephoto';
var imgSelected = 0;

function PhotoMouseOver(photoID) {
    if (photoID == imgSelected) { return false; }
    var photo = document.getElementById(imgPrefix + photoID);
    photo.setAttribute('class', 'PhotoSmall ImgBorderOnMouseOver');
    photo.className = 'PhotoSmall ImgBorderOnMouseOver'; //ie7
}

function PhotoMouseOut(photoID) {
    if (photoID == imgSelected) { return false; }
    var photo = document.getElementById(imgPrefix + photoID);
    photo.setAttribute('class', 'PhotoSmall');
    photo.className = 'PhotoSmall'; //ie7
}

function PhotoChange(photoID) {
    var photo = document.getElementById(imgPrefix + photoID);
    var photoBig = document.getElementById(imgPrefix + 'big');
    photoBig.src = photo.src.replace('-small.jpg', '.jpg');
    photoBig.title = photo.title;
    document.getElementById('vakantiephotobigtitle').innerHTML = photo.title;

    if (imgSelected != photoID) {
        var photoPrev = document.getElementById(imgPrefix + imgSelected);
        photoPrev.setAttribute('class', 'PhotoSmall');
        photoPrev.className = 'PhotoSmall'; //ie7
    }

    imgSelected = photoID;
}