function showpic(bildnr,anzahl)
{

var bildname = "image" + bildnr;

var alleBilder = document.getElementsByClassName("galerypic");

for (var i=0;i<alleBilder.length;i++)
 {
    alleBilder[i].style.display = "none";
 }

document.images[bildname].style.display = "inline";

var nextpic = Number(bildnr)+1;
var forpic = Number(bildnr)-1;

document.getElementById("galeryleftlink").href = "javascript:showpic("+forpic+","+anzahl+")";
document.getElementById("galeryrightlink").href = "javascript:showpic("+nextpic+","+anzahl+")";
document.images["galeryrightimg"].src = "/img/galery_pfeil.gif";
document.images["galeryleftimg"].src = "/img/galery_pfeil2.gif";

if (bildnr == 1) {
 document.getElementById("galeryleftlink").href = "#";
document.images["galeryleftimg"].src = "/img/galery_pfeil2-off.gif";
 }

if (bildnr == anzahl) {
 document.getElementById("galeryrightlink").href = "#";
document.images["galeryrightimg"].src = "/img/galery_pfeil-off.gif";
 }

}