public void TestStreetError()
        {
            var addr=new Address();
            var errorInfo=addr as System.ComponentModel.IDataErrorInfo;

            Assert.IsTrue(String.IsNullOrWhiteSpace(errorInfo["Street"]));

            addr.Street="error";
             Assert.IsFalse(String.IsNullOrWhiteSpace(errorInfo["Street"]));
        }
 public AddressValidator(Address address)
 {
     _address = address;
     _streetProperty=PropertySupport.ExtractPropertyName(() => _address.Street);
     _cityProperty = PropertySupport.ExtractPropertyName(() => _address.City);
 }