function isValidDate(dateStr) {

var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/;
var matchArray = dateStr.match(datePat); 

if (matchArray == null) 
{
	return false;
}

month = matchArray[1]; 
day = matchArray[3];
year = matchArray[4];

if (month < 1 || month > 12) 
{ 
	return false;
}

if (day < 1 || day > 31) 
{
	return false;
}

if ((month==4 || month==6 || month==9 || month==11) && day==31) 
{
	return false
}

if (month == 2) 
{ 
var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
	if (day>29 || (day==29 && !isleap)) 
	{
		return false;
	}
}
return true;
}

function isInteger (s)
{   
var reInteger = /^\d+$/;
if (s.length > 0)
{
	if (reInteger.test(s) == false) 
	{
		return false;
	}
}
return true;
}

function isWhitespace (s, bag)
{   
	var i;
	var returnString = false;
	for (i = 0; i < s.length; i++)
	{
		var c = s.charAt(i);
		if (bag.indexOf(c) != -1) returnString = true;
	}
	return returnString;
}

function isEmail (s)
{
	var reEmail = /^.+\@.+\..+$/
	return reEmail.test(s)
}

function check_appointment()
{

	if (document.frmAppointment.firstname.value == '')
	{
		alert('Please enter your First Name');
		document.frmAppointment.firstname.focus();
		return false;
	}

	if (document.frmAppointment.lastname.value == '')
	{
		alert('Please enter your Last Name');
		document.frmAppointment.lastname.focus();
		return false;
	}

	if (document.frmAppointment.email.value == '')
	{
		alert('Please enter your Email');
		document.frmAppointment.email.focus();
		return false;
	}


	if (!isEmail(document.frmAppointment.email.value))
	{
		alert('Please enter valid Email address');
		document.frmAppointment.email.focus();
		return false;
	}

	if ((document.frmAppointment.phone1.value == '') || (document.frmAppointment.phone1.value.length < 3) ||  (!isInteger(document.frmAppointment.phone1.value)))
	{
		alert('Please enter valid Area Code');
		document.frmAppointment.phone1.focus();
		return false;
	}

	if (document.frmAppointment.phone2.value == '' || (document.frmAppointment.phone2.value.length < 3) || (!isInteger(document.frmAppointment.phone2.value)))
	{
		alert('Please enter valid Phone Number');
		document.frmAppointment.phone2.focus();
		return false;
	}

	if (document.frmAppointment.phone3.value == '' || (document.frmAppointment.phone3.value.length < 4) || (!isInteger(document.frmAppointment.phone3.value)))
	{
		alert('Please enter valid Phone Number');
		document.frmAppointment.phone3.focus();
		return false;
	}

	if (document.frmAppointment.servicedate.value == '')
	{
		alert('Please choose appointment date from calendar');
		document.frmAppointment.servicedate.focus();
		return false;
	}

	if (!isValidDate(document.frmAppointment.servicedate.value))
	{
		alert('Please choose valid appointment date from calendar');
		document.frmAppointment.servicedate.focus();
		return false;
	}

	return true;

}