Deciding on type in the runtime and applying it in generic type - how can I do this? [duplicate]

Answer 1

Use Type.MakeGenericType(type[]):

Type elementType = GetElementType(); // get this type at runtime
Type listType = typeof(List<>);
Type combinedType = listType.MakeGenericType(elementType);
IList elements = (IList) Activator.CreateInstance(combinedType);

You have to use IList to keep the result - because you don't know the actual type that will be used at runtime.

For generic types with more than one type parameter you would use something like Dictionary<,>.

See also http://msdn.microsoft.com/en-us/library/system.type.makegenerictype.aspx