Question

Ok, I’m trying to use reflection to iterate through a class to get all properties and values of that class and sub classes. The problem I am running into is getting the values of a class that is a subclass of the object I’m working with. For Example. I want to get the ClassRoom properties for the Teacher object in the example below.

Another issue I’m having is how to determine when I get to a containable property such as the List of Students so I can then have it iterate through the list.

ex:

public class Teacher 
{
    public int ID {get;set;}
    public string FullName {get;set;}
    public ClassRoom HomeRoom {get;set;}
    public List<Student> Students {get;set;}
}
public class ClassRoom
{
    public int ID {get;set;}
    public string RoomNumber {get;set;}
}
public class Student
{
    public int ID {get;set;}
    public string FullName {get;set;}
}

private void LoadTeacher()
{
    Teacher thisTeacher = Session["Teacher"] as Teacher;
    Type type = thisTeacher.GetType();

    PropertyInfo[] props = type.GetProperties();
    foreach (PropertyInfo prop in props)
    {
        if (prop.PropertyType.IsClass && prop.PropertyType != typeof(string))
        {
            Type headerType = prop.PropertyType;
            PropertyInfo[] headerProps = headerType.GetProperties();
            //Instantiate an object of the headerType
            object headerObj = Activator.CreateInstance(headerType);
            foreach (PropertyInfo childProp in headerProps)
            {
                if (!childProp.PropertyType.IsClass || childProp.PropertyType == typeof(string))
                {
                    //This object always get loaded with default values, Why?
                    object value = childProp.GetValue(headerObj, null);                                                    
                }
            }
        }
    }
}

Answer 1

   var teacher = new Teacher()
    {
      HomeRoom = new ClassRoom { ID = 12, RoomNumber = "7-1" },
      Students = new List<Student> { new Student{ID =1, FullName = "Smith1"}, new Student{ID=2, FullName = "Smith2"} }
    };
    Console.WriteLine("Teacher");
    Browse(teacher, 1);

 static void Browse(object item, int level = 0)
  {
    if (item == null)
      return;
    var prefix = new string(' ', level * 2);

    var type = item.GetType();
    foreach (var prop in type.GetProperties())
    {
      var value = prop.GetValue(item, null);
      if (value is System.Collections.IEnumerable && !(value is string))
      {
        Console.WriteLine("{0}{1}", prefix, prop.Name);
        foreach (var index_entry in ((System.Collections.IEnumerable)value).OfType<object>().Select((entry, index) => new { entry, index }))
        {
          Console.WriteLine("{0}[{1}]: {2}", prefix, index_entry.index, index_entry.entry);
          Browse(index_entry.entry, level + 1);
        }
      }
      else if (value != null && !value.GetType().IsPrimitive && !(value is string))
      {
        Console.WriteLine("{0}{1}: {2}", prefix, prop.Name, value);
        Browse(value, level + 1);
      }
      else
      {
        Console.WriteLine("{0}{1}: {2}", prefix, prop.Name, value);
      }

    }
  }

Output

Teacher
  ID: 0
  FullName:
  HomeRoom: Program+ClassRoom
    ID: 12
    RoomNumber: 7-1
  Students
  [0]: Program+Student
    ID: 1
    FullName: Smith1
  [1]: Program+Student
    ID: 2
    FullName: Smith2