function toggledisplay(togId) {
	document.getElementById(togId).style.display = "block"
}

function togglehide(togId) {
	document.getElementById(togId).style.display = "none"
}

function loadImages() {
	if (document.getElementById) {  // DOM3 = IE5, NS6
		document.getElementById('hidepage').style.visibility = 'hidden';
	} else {
		if (document.layers) {  // Netscape 4
			document.hidepage.visibility = 'hidden';
		} else {  // IE 4
			document.all.hidepage.style.visibility = 'hidden';
		}
	}
}

function getRadioValue(objRadio) {
	for(var i=0;i<objRadio.length;i++)	{
		if (objRadio[i].checked){
			return (objRadio[i].value);
		}
	}
}

function checkRSVP(theform){
	var emailID=theform.email
	
	if ((theform.name.value==null)||(theform.name.value=="")){
		alert("Please enter your name.");
		theform.name.focus();
		return false;
	}
	if ((theform.company.value==null)||(theform.company.value=="")){
		alert("Please enter your company name.");
		theform.company.focus();
		return false;
	}
	if ((theform.contactno.value==null)||(theform.contactno.value=="")){
		alert("Please enter your contact no.");
		theform.contactno.focus();
		return false;
	}
	if ((emailID.value==null)||(emailID.value=="")){
		alert("Please enter your email address.");
		emailID.focus();
		return false;
	}
	if (echeck(emailID.value)==false){
		emailID.value="";
		emailID.focus();
		return false;
	}
	if (!(getRadioValue(theform.agree))) {
		alert("You will need to tick either the yes or no box.");
		theform.agree[0].focus();
		return false;
	}
	return true;
}

function checkNo(field) {
  	var valid = "0123456789";
  	var ok = "yes";
  	var temp;
		
  	for (var i=0; i<field.value.length; i++){
		temp = "" + field.value.substring(i, i+1);
		if (valid.indexOf(temp) == "-1") ok = "no";
	}
  	if (ok == "no"){
  		//alert("Invalid entry!  Only numbers are accepted!");
  		field.value = field.value.substring(0, field.value.length - 1);
  		field.focus();
	}
}

function echeck(str) {
	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	if (str.indexOf(at)==-1){
		alert("Invalid Email")
		return false
	}
	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		alert("Invalid Email")
		return false
	}
	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		alert("Invalid Email")
		return false
	}
	if (str.indexOf(at,(lat+1))!=-1){
		alert("Invalid Email")
		return false
	}
	if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		alert("Invalid Email")
		return false
	}
	if (str.indexOf(dot,(lat+2))==-1){
		alert("Invalid Email")
		return false
	}
	if (str.indexOf(" ")!=-1){
		alert("Invalid Email")
		return false
	}
	return true					
}