Use a string from a config file to initilize a gen

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Pass An Instantiated System.Type as a Type Parameter for a Generic Class (6 answers)

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I have a class:

public class MyClass<T>

I have a config file that I am reading that has, say, Guid for the type T.

How do I do this, except using the string from the config file instead of the actual type (instead of hard-coding Guid)?

MyClass<Guid> = new MyClass<Guid>();

Answer 1

You need the fully qualified type name:

var typeArgument = Type.GetType("System.Guid");

Then you can use reflection to get the parameterized type:

var genericType = typeof(MyClass<>).MakeGenericType(typeArgument);

Which you can then instantiate via:

var instance = Activator.CreateInstance(genericType);

But I'm not sure why you would want to do this or why it would be useful in your scenario. Since using this technique, you'll never be able to interact with MyClass<T> where T is defined as something you're specifying at compile-time, you lose most of the advantages of using generics in the first place.