图片变换的js，内附有5张图片，用一张图片作为目标图片，然后移动鼠标到任意四张图片上，那么目标图片便会变成鼠标选中的图片-Picture transform js, containing five pictures, use a picture as the target picture, then move the mouse to any four pictures, then the target image will become the mouse to select the pict