Web reference proxy is field specified

Question

I have a WCF service. And in my mobile application I generated a Web References.

I notice that for some fields it also generates a myFieldSpecified bool. For example, i have a class Quantity that contains an int quantity. on the mobile side it also generates a bool quantitySpecified.

What is the purpose of this specified field?

Answer 1

This happens if quantity field is not marked as required on the service. Service description than uses this field as nullable and web reference divide the nullable type into non nullable and bool which is saying if field was specified.