>>number is not an integer; it's a nullable integer because of the ?
>> int? value = null;
>> Console.WriteLine(value.HasValue);
>> value = 1;
>> Console.WriteLine(value.HasValue);
>> Console.WriteLine(value)
>>
>>When I run this I get
>>false
>>true
>>1
>
>It appears this syntax is C# only. Could it be?

the ? appears to c# only.

This this alternate form

https://msdn.microsoft.com/en-us/library/b3h38hb0%28v=vs.110%29.aspx