var txtName;
var txtMembershipNumber;
var txtEmailAddress;
var txtAddress;
var txtTelephone;
var txtMessage;
var frmContact;

window.onload=function() {
	txtName=document.getElementById('txtName');
	txtMembershipNumber=document.getElementById('txtMembershipNumber');
	txtEmailAddress=document.getElementById('txtEmailAddress');
	txtAddress=document.getElementById('txtAddress');
	txtTelephone=document.getElementById('txtTelephone');
	txtMessage=document.getElementById('txtMessage');
	frmContact=document.getElementById('frmContact');
	
	frmContact.onsubmit=frmContact_onsubmit;
}

function frmContact_onsubmit() {
	if(txtName.value.length==0) {
		alert('Please provide your name.');
		txtName.focus();
		return(false);
	}
	else if(txtEmailAddress.value.length==0) {
		alert('Please provide your e-mail address.');
		txtEmailAddress.focus();
		return(false);
	}
	else if(!validateEmail(txtEmailAddress.value)) {
		alert('The e-mail address you provided is not valid.');
		txtEmailAddress.focus();
		return(false);
	}
	else if(txtAddress.value.length==0) {
		alert('Please provide your address.');
		txtAddress.focus();
		return(false);
	}
	else if(txtMessage.value.length==0) {
		alert('Please write a message.');
		txtMessage.focus();
		return(false);
	}
	else {
		return(true);
	}
}

function validateEmail(str) {
	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	if (str.indexOf(at)==-1){
	   return false
	}

	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
	   return false
	}

	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
	    return false
	}

	 if (str.indexOf(at,(lat+1))!=-1){
	    return false
	 }

	 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
	    return false
	 }

	 if (str.indexOf(dot,(lat+2))==-1){
	    return false
	 }
	
	 if (str.indexOf(" ")!=-1){
	    return false
	 }

		 return true					
}