function validate_required(field,defaultvalue,alerttxt)
{
with (field)
{
  if (value==null||value=="" || value==defaultvalue)
  {
  alert(alerttxt);return false;
  }
  else
  {
  return true;
  }
}
}


function validate_email(field,alerttxt)
{
with (field)
{
apos=value.indexOf("@");
dotpos=value.lastIndexOf(".");
if (apos<1||dotpos-apos<2) 
  {alert(alerttxt);return false;}
else {return true;}
}
}


function validate_num(field,alerttxt)
{
with (field)
{
if (isNaN(value)) 
  {alert(alerttxt);return false;}
else {return true;}
}
}

function validate_form(thisform)
{
with (thisform)
{
   if (validate_required(document.getElementById('firstname'),"First Name","First name is required")==false)
      {document.getElementById('firstname').focus();return false;}
      else if (validate_required(document.getElementById('lastname'),"Last Name", "Last name is required")==false)
            {document.getElementById('lastname').focus();return false;}
         

}
}