how to implement inheritance between two Structs

Question

Please, I want to implement inheritance between two Structs. Performance is highly important.

Sample code:

struct IntColl
{
}

struct ValidIntColl : IntColl
{
}

Message from Visual Studio:

Error 1 Type 'IntColl' in interface list is not an interface

How do I get this error? IntColl is a Struct, not an Interface!

Right there in the docs: "Structs can implement an interface but they cannot inherit from another struct." — D Stanley, Sep 30 '13 at 20:22
Are you sure you understand the pros and cons (in terms of performance) involved here? I stand unconvinced. — Ed S., Sep 30 '13 at 20:22

score 4 · Answer 1 · edited May 23 '17 at 10:26

4

Structs can only implement interfaces, they can't inherit other structs.

For more information, please see these other questions:

edited May 23 '17 at 10:26

Community

1
1

answered Sep 30 '13 at 20:22

valverij

4,871
1
22
35

score 1 · Answer 2 · answered Sep 30 '13 at 20:22

1

struct (C# Reference)

Structs can implement an interface but they cannot inherit from another struct.

So you simply can't inherit from struct to create another struct.

answered Sep 30 '13 at 20:22

MarcinJuraszek

124,003
15
196
263

score 1 · Answer 3 · answered Sep 30 '13 at 20:29

1

You can also use composition, since inheritance won't work here:

struct IntColl
{
}

struct ValidIntColl
{
    IntColl MyIntCollField;
}

answered Sep 30 '13 at 20:29

mao47

967
10
25

score 0 · Answer 4 · answered Sep 30 '13 at 20:22

0

C# doesn't have struct inheritance. You'll need to change them into classes. Speed shouldn't be impacted all that much.

answered Sep 30 '13 at 20:22

System Down

6,192
1
30
34

score 0 · Answer 5 · answered Sep 30 '13 at 20:26

I want to create a struct that inherits from another struct so it gets put on the stack

You cant:

Structs can implement an interface but they cannot inherit from another struct.

per MSDN

Speed is of high importance

You are assuming that structs are slower than classes. While there may be some speed difference, I would not make this assumption categorically. What you are doing with the clases/structs is very likely to be slower than the memory access.

If inheritance is a key requirement, then you'll need to build your objects as classes rather than structs. Or use another pattern like encapsulation (have one struct be a property of another).

If you get to the point that you can prove that classes will be slower that structs in your scenario, your only option may be to replicate the necessary fields in the structure map.

how to implement inheritance between two Structs

5 Answers5