function valButton(btn) {
    var cnt = -1;
    for (var i=btn.length-1; i > -1; i--) {
        if (btn[i].checked) {cnt = i; i = -1;}
    }
    if (cnt > -1) return btn[cnt].value;
    else return null;
}
      
function validate1(address) {
   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
   var result=address.match(reg);
   if(result==null) {
     
      return false;
   }
   return true;
}
function validatephone(ph) {
 var numericExpression = /^[0-9]+$/;
   var result=ph.match(numericExpression);
   if(result==null) {
     
      return false;
   }
   return true;
}


function validate()
{
	var obj=document.form1;
	
	var btn = valButton(obj.radio1);
	if(btn == null)
	{
	alert('No radio button selected');
	return false;
	}
	
	if(obj.flightfrom.value==0)
	{
		alert("Please Enter flight from");
		obj.flightfrom.focus();
		return false;
	}
	if(obj.flightto.value==0)
	{
		alert("Please Enter flightto");
		obj.flightto.focus();
		return false;
	}
	if(obj.name.value==0)
	{
		alert("Please Enter name");
		obj.name.focus();
		return false;
	}
	if(obj.phone.value==0)
	{
		alert("Please Enter phone number!");
		obj.phone.focus();
		return false;
	}
	
		phoneno=obj.phone.value;
	 if(!validatephone(phoneno))
	 {
	  alert("Please enter a valid phone number!");
	  obj.phone.focus();
	  return false;
 }
	email1=obj.email.value;
	if(!validate1(email1))
		{
			alert("Invalid email");
			obj.email.focus();
			return false;
		}
	
	 var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
	 if(obj.email.match(emailExp)==null)
		 {
	  alert("Please enter a valid email address!");
	  document.getElementById("email").focus();
	  return false;
 		}
 return true;
}