var submitted = false;

function mouseoverRegisterForm() {
if(submitted == true) { return; }
document.getElementById('submitbutton').src='img/registration_submit_on.gif';
}

function mouseoutRegisterForm() {
if(submitted == true) { return; }
document.getElementById('submitbutton').src='img/registration_submit_off.gif';
}

function submitRegisterForm() {
if(submitted == true) { return; }
document.register.submit();
document.getElementById('submitbutton').src='img/registration_submit_off.gif';
document.getElementById('submitbutton').disabled = true;
submitted = true;
}

function submitRegisterFormch() {
if(submitted == true) { return; }
document.register.submit();
document.getElementById('submitbutton').disabled = true;
submitted = true;
}

function setBookmark(url,str){
if(str=='') str=url;
	if (document.all) {
	window.external.AddFavorite(url,str);
	} else {
	alert('To add a bookmark\nPC: Press CTRL and D.\nMac: Press Apple and D.\n"'+url+'"');
	}
} 

function OthersOn() {
    document.register.elements['registerform[diet]'].checked = false;
    var divid = document.getElementById('otherdietfield').style;
    divid.display = "inline";
    
    if (document.register.elements['registerform[odiet]'].checked == true) {
    document.register.elements['registerform[odiet]'].checked = true;
	} else {
	document.register.elements['registerform[odietfield]'].value = "";
	var divid = document.getElementById('otherdietfield').style;
    divid.display = "none";
	}
}

function OthersOff() {
	document.register.elements['registerform[odiet]'].checked = false;
    document.register.elements['registerform[odietfield]'].value = "";
    var divid = document.getElementById('otherdietfield').style;
    divid.display = "none";
}

function externalLinks() { 
if (!document.getElementsByTagName) return; 
var anchors = document.getElementsByTagName("a"); 
for (var i=0; i<anchors.length; i++) { 
	var anchor = anchors[i]; 
	if (anchor.getAttribute("href") && 
		anchor.getAttribute("rel") == "external") 
		anchor.target = "_blank"; 
	} 
} 
window.onload = externalLinks;
 
function confirming(url,message) {
	var confirmation=confirm(message); 
 	if (confirmation) {
 	window.location.href=url;
 	} 
}

function open_pop(theURL,winName,w,h,scroll,resize) { //v2.0
var winl = ((screen.width/2) - (w/2));
var wint = ((screen.height/2) - (h/2) - 10);
winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars='+scroll+',resizable='+resize+''
win=window.open(theURL,winName,winprops);
if (parseInt(navigator.appVersion) >= 4) { win.window.focus(); }
}

function check_empty(text) {
  return (text.length > 0); 
}

function verify_friend_form(){
  if (!check_empty(document.sendtofriend.fromName.value)) { 
    alert('Please Enter your Name.'); 
    return false;
  } else if (!check_empty(document.sendtofriend.toName.value)) {  
  	alert('Please Enter your Friend\'s Name.'); 
  	return false; 
  } else if (!check_empty(document.sendtofriend.toEmail.value)) {
  	alert('Please Enter your Friend\'s Email Address.'); 
  	return false;
  } else if (!/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.sendtofriend.toEmail.value)) {  
  	alert('Please Enter a Valid Email address for your Friend.');
  	return false;
  } else {
  	return true; 
  }
}

function verify_update_form(){
  if (!check_empty(document.updateform.title.value)) { 
    alert('Please select a Title.'); 
    return false;
  } else if (!check_empty(document.updateform.fname.value)) {  
  	alert('Please enter your First Name.'); 
  	return false; 
  } else if (!check_empty(document.updateform.surname.value)) {
  	alert('Please enter your Surname.'); 
  	return false;
  } else if (!check_empty(document.updateform.company.value)) {
  	alert('Please enter your Company/Organisation.'); 
  	return false;
  } else if (!check_empty(document.updateform.position.value)) {
  	alert('Please enter your Position.'); 
  	return false;
  } else if (!check_empty(document.updateform.telephone.value)) {
  	alert('Please enter your telephone number.'); 
  	return false;
  } else if (!check_empty(document.updateform.email.value)) {
  	alert('Please enter your Email Address.'); 
  	return false;
  } else if (!/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.updateform.email.value)) {  
  	alert('Please enter a valid Email Address.');
  	return false;
  } else if (!check_empty(document.updateform.address.value)) {
  	alert('Please enter your Address.'); 
  	return false;
  } else if (!check_empty(document.updateform.country.value)) {
  	alert('Please enter your Country.'); 
  	return false;
  } else if (!check_empty(document.updateform.notified.value)) {
  	alert('Please select from the drop down list how you heard about the conference.'); 
  	return false;
  } else {
  	return true; 
  }
}