Reflection & WASM, assembly got linked.

[CobraCalle]

I have a class like this…

[Operation("+", 20)]
public class Add : Operation
{
    internal Add(Formula formula, Value left, Value right)
        : base(formula, left, right)
    {
    }

}

Now I what to create this type by reflection and try to get the constructor…

                System.Reflection.ConstructorInfo constructor = operation.GetConstructor(System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic, null, new Type[] { typeof(Diomex.Framework.Math.FormulaParser.Formula), typeof(Diomex.Framework.Math.FormulaParser.Value), typeof(Diomex.Framework.Math.FormulaParser.Value) }, null);

"operation" is here typeof(Add)

This works well… except in the WASM-version… there is constructor null

Any ideas?

[carldebilly]

That's because your assembly got linked during compilation. This means the linker considers this constructor is never called and get rid of it.

You can hint the linker like we did in the playground:

1. Create a file called LinkerConfig.xml like this: https://github.com/nventive/Uno.Playground/blob/master/src/Uno.Playground.WASM/LinkerConfig.xml and add relevant assemblies/namespaces/types. You can find the documentation here: https://github.com/mono/linker/tree/master/linker#syntax-of-xml-descriptor
2. Reference your file in the .csproj like this: https://github.com/nventive/Uno.Playground/blob/master/src/Uno.Playground.WASM/Uno.Playground.WASM.csproj#L43

Another way to do that would be to add a [Preserve] attribute on your class. https://github.com/nventive/Uno/blob/master/src/Uno.Foundation/PreserveAttribute.cs