function validate(){

	obj_email = document.getElementById('email');	
	obj_firstName = document.getElementById('firstName');
	obj_lastName = document.getElementById('lastName');		
	obj_phoneNo = document.getElementById('phoneno');
	obj_message = document.getElementById('message');
	
	
	
	if(obj_firstName.value==""){
		alert('Please enter your First Name.');
		obj_firstName.focus();
		return false;
	}	
	
	if(obj_lastName.value==""){
		alert('Please enter your Last Name.');
		obj_lastName.focus();
		return false;
	}		
	
	if(obj_email.value==""){
		alert('Please enter your Email address.');
		obj_email.focus();
		return false;
	}
	else{	
		var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;	
		if(!obj_email.value.match(emailExp))
			{
			alert("Please enter your valid Email address.");
			obj_email.focus();
			obj_email.select();
			return false;
		}
	}
		
	
	if(obj_phoneNo.value!=''){
		
		if(checkField('phoneno')==false){		
			alert("Please enter your 10 digit Phone numbers, Only -,() character is acceptable");
			obj_phoneNo.focus();
			return false;
		}			
	}
	
	if(obj_message.value==""){
		alert('Please enter your Comments.');
		obj_message.focus();
		return false;
	}
	
	return true;
}




function checkField(fldid)
{
	var contactNumber= document.getElementById(fldid).value;
	if (contactNumber.length != 0)

	{
		var telnum = contactNumber;

		// Remove spaces from the telephone number to help validation
		while (telnum.indexOf(" ")!= -1)
		{
			telnum = telnum.slice (0,telnum.indexOf(" ")) + telnum.slice (telnum.indexOf(" ")+1);
		}

		// Remove hyphens from the telephone number to help validation
		while (telnum.indexOf("-")!= -1)
		{
			telnum = telnum.slice (0,telnum.indexOf("-")) + telnum.slice (telnum.indexOf("-")+1);
		}

		while (telnum.indexOf("(")!= -1)
		{
			telnum = telnum.slice (0,telnum.indexOf("(")) + telnum.slice (telnum.indexOf("(")+1);
		}

		while (telnum.indexOf(")")!= -1)
		{
			telnum = telnum.slice (0,telnum.indexOf(")")) + telnum.slice (telnum.indexOf(")")+1);
		}
		
		// Now check that all the characters are digits
		exp = /^[0-9]$/;
		if (exp.test(telnum) != true && telnum.length!=10)
		{			
			return false
		}
	}
	return true

}