Just as Diodeus said, you’re comparing an Image
to a HTMLDomObject
. Instead compare their .src
attribute:
var imgArray = new Array(); imgArray[0] = new Image(); imgArray[0].src = 'images/img/Splash_image1.jpg'; imgArray[1] = new Image(); imgArray[1].src = 'images/img/Splash_image2.jpg'; /* ... more images ... */ imgArray[5] = new Image(); imgArray[5].src = 'images/img/Splash_image6.jpg'; /*------------------------------------*/ function nextImage(element) { var img = document.getElementById(element); for(var i = 0; i < imgArray.length;i++) { if(imgArray[i].src == img.src) // << check this { if(i === imgArray.length){ document.getElementById(element).src = imgArray[0].src; break; } document.getElementById(element).src = imgArray[i+1].src; break; } } }