function appointment()
{
if(document.getElementById("txtfname").value=="")
   {
      alert("PLEASE ENTER FIRST NAME") 
      return false;
   }
if(document.getElementById("txtlname").value=="")
   {
      alert("PLEASE ENTER LAST NAME") 
      return false;
   }  
if(document.getElementById("textarea").value=="")
   {
      alert("PLEASE ENTER YOUR ADDRESS") 
      return false;
   }
   
var regex = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
if(document.getElementById("txtemailone").value=="")
{
	alert("PLEASE ENTER YOUR EMAIL ADDRESS");
	return false;
}
else if(!regex.test(document.getElementById("txtemailone").value))
{
	alert("Invalid email address format");
	return false;
} 

if(document.getElementById("textarea").value=="")
   {
      alert("PLEASE ENTER YOUR ADDRESS") 
      return false;
   }
   
if(document.getElementById("txtcity").value=="")
   {
      alert("PLEASE ENTER YOUR CITY") 
      return false;
   } 
   
if(document.getElementById("txtzip").value=="")
   {
      alert("PLEASE ENTER YOUR ZIPCODE") 
      return false;
   }    
  
   
}