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c#c++unions

C++ union in C#

I'm translating a library written in C++ to C#, and the keyword 'union' exists once. In a struct.

What's the correct way of translating it into C#? And what does it do? It looks something like this;

struct Foo {
    float bar;

    union {
        int killroy;
        float fubar;
    } as;
}
Solution

  • You can use explicit field layouts for that:

    [StructLayout(LayoutKind.Explicit)] 
public struct SampleUnion
{
    [FieldOffset(0)] public float bar;
    [FieldOffset(4)] public int killroy;
    [FieldOffset(4)] public float fubar;
}

    Untested. The idea is that two variables have the same position in your struct. You can of course only use one of them.

    More informations about unions in struct tutorial