How to store a List of classes in C#?

Question

In Java I am able to have a list of classes like:

List<Class>

But how do I do this in C#?

Answer 1

Storing the class types

If you mean a list of actual classes, not instances of a class, then you can use Type instead of Class. Something like this:

List<Type> types = new List<Type>();
types.Add(SomeClass.GetType());
types.Add(SomeOtherClass.GetType());

Instantiating the types

To actually instantiate a class given a classes Type you can use Activator or reflection. See this post for information on that. It can get a little complicated however when the compiler doesn't know about the constructors/parameters and such.

// Create an instance of types[0] using the default constructor
object newObject = Activator.CreateInstance(types[0]);

Or alternatively

// Get all public constructors for types[0]
var ctors = types[0].GetConstructors(BindingFlags.Public);

// Create a class of types[0] using the first constructor
var object = ctors[0].Invoke(new object[] { });

Answer 2

The same basic syntax works in C#:

List<YourClass> list = new List<YourClass>();

This requires you to have using System.Collections.Generic; at the top of your file, which is the namespace which provides most of the generic collections.

If you are attempting to store a list of types, you can use List<System.Type>. Instances of those types could then be constructed via Activator.CreateInstance (which accepts the type) as needed.

Answer 3

    // Create the list
    List<ClassName> classList = new List<ClassName>();

    // Create instance of your object
    ClassName cn = new ClassName();

    // Add the object to the list
    classList.Add(cn);