//---------------------------  validacion del mail ------------------------------------------
function EsValidoEmail(FormName,ElemName)
  {
    var EmailOk  = true;
    var Temp     = document.forms[FormName].elements[ElemName];
    var AtSym    = Temp.value.indexOf('@');
    var Period   = Temp.value.lastIndexOf('.');
    var Space    = Temp.value.indexOf(' ');
    var Length   = Temp.value.length - 1;   // Array is from 0 to length-2

    if ((AtSym < 2) ||                      // Antes de '@' deben haber por lo menos 2 car.
        (Period <= AtSym+1) ||              // Deben haber por menos 1 car. entre '@' y '.'
        (Period == Length ) ||              // Despues del "." debe haber por lo menos 2 car.
        (Space  != -1))                     // No empty spaces permitted
    {  
      EmailOk = false;
    }
    return EmailOk;
  }
  
//------------------------------ activación y desactivación de campos de texto --------------------------------------------

function desactiva_Input(formu)
{
  formu.imagen1.disabled = true;
  formu.imagen2.disabled = true;
  formu.imagen3.disabled = true;
  formu.imagen4.disabled = true;
}

function activa_Input(formu)
{
  formu.imagen1.disabled = false;
  formu.imagen2.disabled = false;
  formu.imagen3.disabled = false;
  formu.imagen4.disabled = false;
}

//-----------------------------------------  galeria de imagenes ------------------------------------------------------------

// NO NECESITAS EDITAR DEBAJO DE ESTA LÍNEA!
function CacheImage(ImageSource) { // TURNS THE STRING INTO AN IMAGE OBJECT
   var ImageObject = new Image();
   ImageObject.src = ImageSource;
   return ImageObject;
}

function ShowSlide(Direction) {
   if (SlideReady) {
      NextSlide = CurrentSlide + Direction;
      // THIS WILL DISABLE THE BUTTONS (IE-ONLY)
//      document.SlideShow.Previous.disabled = (NextSlide == 0);
//      document.SlideShow.Next.disabled = (NextSlide == (Slides.length-1));    
 if ((NextSlide >= 0) && (NextSlide < Slides.length)) {
            document.images['Screen'].src = Slides[NextSlide].src;
            CurrentSlide = NextSlide++;
            Message = 'Picture ' + (CurrentSlide+1) + ' of ' + 
Slides.length;
            self.defaultStatus = Message;
            if (Direction == 1) CacheNextSlide();
      }
      return true;
   }
}

function Download() {
   if (Slides[NextSlide].complete) {
      SlideReady = true;
      self.defaultStatus = Message;
   }
   else setTimeout("Download()", 100); // CHECKS DOWNLOAD STATUS EVERY 100 MS
   return true;
}

function CacheNextSlide() {
   if ((NextSlide < Slides.length) && (typeof Slides[NextSlide] == 
'string'))
{ // ONLY CACHES THE IMAGES ONCE
      SlideReady = false;
      self.defaultStatus = 'Downloading next picture...';
      Slides[NextSlide] = CacheImage(Slides[NextSlide]);
      Download();
   }
   return true;
}

function StartSlideShow() {
   CurrentSlide = -1;
   Slides[0] = CacheImage(Slides[0]);
   SlideReady = true;
   ShowSlide(1);
}