function validate()
{
  var name = document.getElementById("txtName");
  var email = document.getElementById("txtEmail");	
  var emailRepeat = document.getElementById("txtEmailRepeat");
  var phone = document.getElementById("txtPhone");
  var mobile = document.getElementById("txtMobile");

  if (name.value == null || name.value == "")
  {
  	alert("Please enter your name.");
  	name.focus();
    return false;
  }
  else if (email.value == null || email.value == "")
  {
  	alert("Please enter your email.");
  	email.focus();
    return false;
  }
  else if (email.value != emailRepeat.value)
  {
  	alert("Emails are not matching.");
  	emailRepeat.focus();
    return false;
  }
  else if (!((email.value.indexOf(".") > 2) && (email.value.indexOf("@") > 0)))
  {
  	alert("Invalid email address. Please enter again.");
  	email.focus();
    return false;
  }
  
  if (phone.value != null || phone.value != "")
  {
	var replaced = phone.value.replace(/[\(\)\.\-\ ]/g, '');

	if (isNaN(replaced)) 
	{
   		alert("Invalid phone number. Please enter again.");
		return false;
	}
  }
  
  if (mobile.value != null || mobile.value != "")
  {
	var replaced = mobile.value.replace(/[\(\)\.\-\ ]/g, '');

	if (isNaN(replaced)) 
	{
   		alert("Invalid mobile number. Please enter again.");
		return false;
	}
  }
  
  return true;
}