Converting Dynamic Types to Generic Parameters

There is a problem when an API uses a Generic Parameter as a Type reference.image Although having a generic parameter makes the code Type Safe

SafeType MyApi<SafeType>();

It is really hard to use the API in dynamic way. So if we receive a Type in a variable there is no easy way to call the generic method.

Type myType = GetTypeToUse();
var ret = MyApi<myType>(); 
//              ^^^^^^ Error

One way to do this (convert a dynamic type to a generic type) is via reflection (See example on the Typemock Blog)

private static object MyApi(Type ofType)
 MethodInfo myApiMethod = typeof(MyAssembly)
 return myApiMethod.Invoke(null, null);

or we can cache the MethodInfo

private static MethodInfo myApi = typeof(MyAssembly).GetMethod("MyApi");
private static object MyApi(Type ofType) { MethodInfo myApiMethod = myApi.MakeGenericMethod(ofType); return myApiMethod.Invoke(null, null); }

When designing an API we should think of developers who receive the Type in a dynamic way, and have an embedded API to handle this from the start.

// Type Safe API
SafeType MyApi<SafeType>();
// Dynamic Type API 
object MyApi(Type ofType);

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