Create delegate with types known at runtime

Question

How can I create a Delegate with types only known at run time ?

I would like to do the following :

Type type1 = someObject.getType();
Type type2 = someOtherObject.getType();   

var getter = (Func<type1, type2>)Delegate.CreateDelegate(
    typeof(Func<,>).MakeGenericType(type1, type2), someMethodInfo);

How can I achieve something similar ?

Answer 1

I suspect you want Expression.GetFuncType as a simpler way of doing your typeof(...).MakeGenericType operation.

var delegateType = Expression.GetFuncType(type1, type2);
Delegate getter = Delegate.CreateDelegate(delegateType, someMethodInfo);

You can't have a compile-time type for getter that's more specific than Delegate though¹, because you simply don't know that type at compile-time. You could potentially use dynamic though, which would make it easier to invoke the delegate:

dynamic getter = ...;
var result = getter(input);

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¹ As noted in comments, you could cast to MulticastDelegate, but it wouldn't actually buy you anything.