function validate_email(field,alerttxt)
{
  with (field)
  {
  apos=value.indexOf("@");
  dotpos=value.lastIndexOf(".");
  if (apos<1||dotpos-apos<2) 
    {alert(alerttxt);return false;}
  else {return true;}
  }
}

function validate_text(field,alerttxt)
{
  with (field)
  {
    if (value=='') 
    {
      alert(alerttxt);
      return false;
    }
    else
    {
      return true;
    }
  }
}

function validate_form(thisform)
{
  with (thisform)
  {
    if (validate_text(link_url,"Please complete all required fields.")==false)
    {link_url.focus();return false;}
  
    if (validate_text(title,"Please complete all required fields.")==false)
    {title.focus();return false;}
    
    if (validate_text(description,"Please complete all required fields.")==false)
    {description.focus();return false;}
    
    if (validate_text(num_pics,"Please complete all required fields.")==false)
    {num_pics.focus();return false;}
    
    if (validate_text(contact_name,"Please complete all required fields.")==false)
    {contact_name.focus();return false;}
  
    if (validate_email(contact_email,"Not a valid e-mail address!")==false)
    {contact_email.focus();return false;}
    
  }
}