Using reflection to set a property of a property of an object

Question

I've got two classes.

public class Class1 {
   public string value {get;set;}
}

public class Class2 {
   public Class1 myClass1Object {get;set;}
}

I've got an object of type Class2. I need to use reflection on Class2 to set the value property... i.e, if I were doing it without reflection, this is how I would go about it:

Class2 myObject = new Class2();
myObject.myClass1Object.value = "some value";

Is there a way to do the above, while using reflection to access the property "myClass1Object.value" ?

Thanks in advance.

Answer 1

Basically split it into two property accesses. First you get the myClass1Object property, then you set the value property on the result.

Obviously you'll need to take whatever format you've got the property name in and split it out - e.g. by dots. For example, this should do an arbitrary depth of properties:

public void SetProperty(object source, string property, object target)
{
    string[] bits = property.Split('.');
    for (int i=0; i < bits.Length - 1; i++)
    {
         PropertyInfo prop = source.GetType().GetProperty(bits[i]);
         source = prop.GetValue(source, null);
    }
    PropertyInfo propertyToSet = source.GetType()
                                       .GetProperty(bits[bits.Length-1]);
    propertyToSet.SetValue(source, target, null);
}

Admittedly you'll probably want a bit more error checking than that :)

Answer 2

I was looking for answers to the case where to Get a property value, when the property name is given, but the nesting level of the property is not known.

Eg. if the input is "value" instead of providing a fully qualified property name like "myClass1Object.value".

Your answers inspired my recursive solution below:

public static object GetPropertyValue(object source, string property)
{
    PropertyInfo prop = source.GetType().GetProperty(property);
    if(prop == null)
    {
      foreach(PropertyInfo propertyMember in source.GetType().GetProperties())
      { 
         object newSource = propertyMember.GetValue(source, null);
         return GetPropertyValue(newSource, property);
      }
    }
    else
    {
       return prop.GetValue(source,null);
    }
    return null;
}

Answer 3

   public static object GetNestedPropertyValue(object source, string property)
    {
        PropertyInfo prop = null;
        string[] props = property.Split('.');

        for (int i = 0; i < props.Length; i++)
        {
            prop = source.GetType().GetProperty(props[i]);
            source = prop.GetValue(source, null);
        }
        return source;
    }