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c#typebuilder

Why does my generated assembly with interface implement as methods instead of as property?

The following code creates an assembly called MyAssembly.dll which contains a single interface called IMyType. IMyType has a single property called my property.

string assemblyName = "MyAssembly";

AssemblyBuilder assemblyBuilder =
    AppDomain.CurrentDomain.DefineDynamicAssembly(
        new AssemblyName(assemblyName),
        AssemblyBuilderAccess.RunAndSave
    );

ModuleBuilder moduleBuilder =
    assemblyBuilder.DefineDynamicModule(
        assemblyName,
        $"{assemblyName}.dll",
        true
    );

TypeBuilder typeBuilder =
    moduleBuilder.DefineType(
        $"{assemblyName}.IMyType",
        TypeAttributes.Public |
        TypeAttributes.Interface |
        TypeAttributes.Abstract
    );

PropertyBuilder propertyBuilder =
    typeBuilder.DefineProperty(
        "MyProperty",
        System.Reflection.PropertyAttributes.HasDefault |
        System.Reflection.PropertyAttributes.SpecialName,
        typeof(int),
        null
    );

MethodBuilder getBuilder =
    typeBuilder.DefineMethod(
        "get_MyProperty",
        MethodAttributes.Virtual |
        MethodAttributes.Abstract |
        MethodAttributes.SpecialName,
        typeof(int),
        Type.EmptyTypes
    );
MethodBuilder setBuilder =
    typeBuilder.DefineMethod(
        "set_MyProperty",
        MethodAttributes.Virtual |
        MethodAttributes.Abstract |
        MethodAttributes.SpecialName,
        typeof(int),
        Type.EmptyTypes
    );

propertyBuilder.SetGetMethod(getBuilder);
propertyBuilder.SetSetMethod(setBuilder);

typeBuilder.CreateType();

assemblyBuilder.Save($"{assemblyName}.dll");

When I decompile the assembly in DotPeek I see the code I expect to see:

enter image description here

In another project however that references this assembly I create a class that implements my new IMyType and visual studio creates this: enter image description here

What do I need to do so that visual studio will see this as an auto property instead of two methods?

Solution

  • Probably, you should define your set method as void and taking one argument of type int.

    MethodBuilder setBuilder =
    typeBuilder.DefineMethod(
        "set_MyProperty",
        MethodAttributes.Virtual |
        MethodAttributes.Abstract |
        MethodAttributes.SpecialName,
        typeof(void),
        new[] { typeof(int) }
    );