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Im trying to use the following code:
private Nullable<List<IpAddressRange>> ipAddressRangeToBind; But I am getting the following warning:
The type List must be a non-nullable value type in order to use it as a parameter 'T' in the generic type or method 'System.Nullable'.
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You can declare nullable types using Nullable<t> where T is a type. Nullable<int> i = null; A nullable type can represent the correct range of values for its underlying value type, plus an additional null value. For example, Nullable<int> can be assigned any value from -2147483648 to 2147483647, or a null value.
In C# programs, a List reference can be null. This is not the same as it being empty and having zero elements.
A list is never null. The variable might be null, but a list itself is not null.
The default value of a nullable value type represents null , that is, it's an instance whose Nullable<T>. HasValue property returns false .
List<T> is already a reference type (for any kind of T) - you can only declare Nullable<T> where T is a non-nullable value type (it's declared as Nullable<T> where T : struct).
But that's okay, because if you just declare:
private List<IpAddressRange> ipAddressRangeToBind; then you can still have
ipAddressRangeToBind = null; because reference types are always nullable.
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