Determine if property is generic List<of T> via Reflection and loop list items

Question

I'm looping all the properties in an object via reflection:

For Each p As PropertyInfo In values.[GetType]().GetProperties()
            If p.CanRead Then
               'Do stuff
            End If  
 Next

Can anyone tell me how to determine whether the property in question is a generic List(Of T)? If it is I need to loop the list itself.

I've experimented with GetType and TypeOf but have not managed to get anything working.

Thanks.

**Update and clarification

To clarify, I want to keep this generic. I do not want to specify the type of T, I need to loop the list items and call the ToString method on each item. T could be one of a number of different types (application specific reference types). Is it possible to do this without specifying types?

(VB.NET 2005 with .Net 2.0)

Answer 1

if p.PropertyType = TypeOf List(Of T) then...

Answer 2

Try this complete console application. Sorry it's in C#.

using System;
using System.Reflection;
using System.Collections.Generic;
using System.Collections;

namespace ReflectionTest
{
    public class Object1
    {
        public override string ToString()
        {
            return "This is Object 1";
        }
    }
    public class Object2
    {
        public override string ToString()
        {
            return "This is Object 2";
        }
    }    

    public class ContainerClass
    {
        public List<object> objects { get; set; }
        public int propA { get; set; }
        public string propB { get; set; }
        public string[] propC { get; set; }
    }
    class Program
    {
        static void Main(string[] args)
        {
            // Sample class instance
            ContainerClass c = new ContainerClass();

            // Add some sample data
            c.objects = new List<object>();
            c.objects.Add(new Object1());
            c.objects.Add(new Object2());

            PropertyInfo[] props = c.GetType().GetProperties();

            foreach (PropertyInfo p in props)
            {
                if (typeof(IList).IsAssignableFrom(p.PropertyType) 
                    && p.PropertyType.IsGenericType)
                {
                    IList item = (IList)p.GetValue(c, null);
                    if (item != null)
                    {
                        foreach (object o in item)
                        {
                            Console.WriteLine(o.ToString());
                        }
                    }
                }
            }
            Console.ReadLine();
        }


    }           
}

Answer 3

Here is Roatins answer in VB.Net, Complete Console Application

Imports System
Imports System.Reflection
Imports System.Collections.Generic
Imports System.Collections

Namespace ReflectionTest
    Public Class Object1
     Public Overloads Overrides Function ToString() As String
      Return "This is Object 1"
     End Function
    End Class
    Public Class Object2
     Public Overloads Overrides Function ToString() As String
      Return "This is Object 2"
     End Function
    End Class

    Public Class ContainerClass
     Public Property objects() As List(Of Object)
      Get
      End Get
      Set
      End Set
     End Property
     Public Property propA() As Integer
      Get
      End Get
      Set
      End Set
     End Property
     Public Property propB() As String
      Get
      End Get
      Set
      End Set
     End Property
     Public Property propC() As String()
      Get
      End Get
      Set
      End Set
     End Property
    End Class
    Class Program
     Shared Sub Main(args As String())
      ' Sample class instance
      Dim c As New ContainerClass()

      ' Add some sample data
      c.objects = New List(Of Object)()
      c.objects.Add(New Object1())
      c.objects.Add(New Object2())

      Dim props As PropertyInfo() = c.[GetType]().GetProperties()

      For Each p As PropertyInfo In props
       If GetType(IList).IsAssignableFrom(p.PropertyType) AndAlso p.PropertyType.IsGenericType Then
        Dim item As IList = DirectCast(p.GetValue(c, Nothing), IList)
        If item <> Nothing Then
         For Each o As Object In item
          Console.WriteLine(o.ToString())
         Next
        End If
       End If
      Next
      Console.ReadLine()
     End Sub


    End Class
End Namespace