c# using const with DllImport -

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c# using const with DllImport -

i have code illustration sdk, dll written in c , calls following:

int getattribute(const rawdevcontrol *control, rawdevattribute *attribute)

i'm using

[dllimport(@"dev.dll", setlasterror = true)] internal static extern int getattribute(const rcontrol *control, rattribute *attribute);

but of course of study can not utilize const type when defining reference function.

how can create work c#?

since c# doesn't have concept of const references, don't need worry it. on dll side, code still think have const pointer. thus, import changes this:

[dllimport(@"dev.dll", setlasterror = true)] internal static extern int getattribute(rcontrol control, rattribute attribute);

this, of course, assumes both rcontrol , rattribute have been defined in c#. if structs, follow examples on msdn defining structs utilize p/invoke. if classes, that's different set of problems. in case, best if classes com-based.

c# const dllimport

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