how to create a list of type obtained from reflection

Question

I have a code which looks like this :

Assembly assembly = Assembly.LoadFrom(\"ReflectionTest.dll\");
Type myType = assembly.GetType(@\"ReflectionTest.TestObject\         


        

Answer 1

var listType = typeof(List<>).MakeGenericType(myType)
var list = Activator.CreateInstance(listType);

var addMethod = listType.GetMethod("Add");
addMethod.Invoke(list, new object[] { x });

You might be able to cast to IList and call Add directly instead of looking up the method with reflection:

var list = (IList)Activator.CreateInstance(listType);
list.Add(x);

Answer 2

You need MakeGenericType method:

var argument = new Type[] { typeof(myType) };
var listType = typeof(List<>); 
var genericType = listType.MakeGenericType(argument); // create generic type
var instance = Activator.CreateInstance(genericType);  // create generic List instance

var method = listType.GetMethod("Add"); // get Add method
method.Invoke(instance, new [] { argument }); // invoke add method 

Alternatively you can cast your instance to IList and directly use Add method.Or use dynamic typing and don't worry about casting:

dynamic list = Activator.CreateInstance(genericType);
list.Add("bla bla bla...");

Answer 3

Try this:

var listType = typeof(List<>);
var constructedListType = listType.MakeGenericType(myType);

var myList = (IList)Activator.CreateInstance(constructedListType);
myList.Add(x);

The list will not be strongly-typed but you can add items as objects.